Issue 06/2005 Technical Guide - buderus.dk · 3 Contents Technical Guide Logano S825L / S825L LN boilers and Logano plus SB825L / SB825L LN gas fired condensing boilers – 06/2005

Technical Guide

Heat is our element

Technical GuideIssue 06/2005A4.02.4

Logano S825L and S825L LN boilers and Logano plus SB825L and SB825L LN gas fired condensing boilers

2 Technical Guide Logano S825L / S825L LN boilers and Logano plus SB825L / SB825L LN gas fired condensing boilers – 06/2005

Contents

1 Oil and gas fired special boilers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1.1 Construction and output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.2 Model overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.3 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41.4 Features and characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2 Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

2.1 Principles of condensing technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62.2 Optimum utilisation of condensing technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72.3 Efficiency considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

3 Technical description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3.1 Logano S825L and S825L LN and Logano plus SB825Land SB825L LN gas fired condensing boilers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3.2 Dimensions and specification for Logano S825L and S825L LN boilers . . . . . . . . . . . . . . . . . . . . . . . . . 123.3 Dimensions and specification for Logano plus SB825L and SB825L LN gas fired condensing boilers . . 183.4 Variable connections for all models subject to the rated output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263.5 Boiler parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

4 Burner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

4.1 General requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394.2 Tips regarding the burner selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394.3 Matching pressure-jet burners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394.4 Combustion details for Logano S825L and S825L LN boilers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 404.5 Combustion details for Logano plus SB825L and SB825L LN gas fired condensing boilers . . . . . . . . . . 44

5 Regulations and operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

5.1 Regulation extracts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 485.2 Operational requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

6 Heating control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

6.1 Control systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 526.2 Logamatic telecontrol system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

7 Domestic hot water heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

7.1 Domestic hot water heating systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577.2 DHW temperature control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

8 System examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

8.1 Information regarding all system examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 588.2 Safety equipment to EN 12828 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 598.3 Sizing and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 628.4 Single boiler system with Logano S825L and S825L LN boiler:

Logamatic boiler and heating circuit control unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

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Contents

Technical Guide Logano S825L / S825L LN boilers and Logano plus SB825L / SB825L LN gas fired condensing boilers – 06/2005

8.5 Single boiler system with Logano S825L and S825L LN boiler: Logamatic boiler and heating circuit control unit with hydraulic separation . . . . . . . . . . . . . . . . . . . . 66

8.6 Single boiler system with Logano S825L and S825L LN boiler: Logamatic boiler control unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

8.7 Single boiler system with Logano S825L and S825L LN boiler: Logamatic boiler control unit with hydraulic separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

8.8 Two-boiler system with two Logano S825L and S825L LN boilers: Logamatic boiler and heating circuit control unit with hydraulic separation . . . . . . . . . . . . . . . . . . . . 69

8.9 Two-boiler system with two Logano S825L and S825L LN boilers: Logamatic boiler control unit with hydraulic separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

8.10 Single boiler system with Logano plus SB825L and SB825L LN gas fired condensing boilers: Logamatic boiler control unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

8.11 Single boiler system with Logano plus SB825L and SB825L LN gas fired condensing boilers: Logamatic boiler control unit with hydraulic separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

8.12 Two-boiler system with Logano S825L and S825L LN boilers andLogano plus SB825L and SB825L LN gas fired condensing boilers:Logamatic boiler control unit with hydraulic separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

8.13 Logano plus SB825L and SB825L LN gas fired condensing boilers:Dual-fuel combustion with condensing heat exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

9 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

9.1 Transportation and handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 759.2 Type of boiler room and combustion air supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 769.3 Installed dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 779.4 Optional equipment for safety equipment to EN 12828 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 799.5 Noise attenuation accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 859.6 Additional accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

10 Flue gas system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

10.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

11 Draining condensate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

11.1 Condensate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9111.2 Neutralising system NE 2.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

12 Selection aids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

12.1 Boiler selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9312.2 Boiler selection questionnaire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

13 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

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1


Oil and gas fired special boilers

1 Oil and gas fired special boilers

1.1 Construction and output

The Logano S825 L LN boilers and the Logano plusSB825 L LN gas fired condensing boilers are specialboilers for pressurised combustion acc. to EN 303 andhave been constructed in accordance with the relevantTRD 300; Buderus offers these boilers with a ratedoutput from 750 to 19200 kW. The boilers are designedfor producing low pressure heating water withmaximum temperatures of 110 °C (shutdown

temperature of the high limit safety cut-out) for use incentral heating systems, which meet the requirementsof EN 12828. The overall operating pressure must notexceed 6 bar (or 10 bar).

Please contact your nearest Buderus sales office, if youintend operating with higher pressures (13 or 16 bar).

1.2 Model overview

1.3 Applications

The modular boiler design and its optional equipmentenable an almost universal application. A suitableversion is offered for almost every requirement.

Preferred applications are larger systems, such as inhospitals, industrial plant, district heating, combinedheat and power stations and commercial operations.

Model description S825LBoiler output

from... to

S825L LNBoiler output

from... to

SB825LBoiler output

from... to

SB825L LNBoiler output

from... to

Max. rated output kW 1000 19200 750 17500 1000 19200 750 17500

Combustion chamber — — yes yes

Condensing heat exchanger

—

Low combustion chamber volume load

for minimum NOX values

—

Low combustion chamber volume load

for minimum NOX values

Safety temperature °C ≤ 110

Safety pressure bar ≤ 10

Dimensions ➔ Page 12 ➔ from Page 14 ➔ from Page 18 ➔ from Page 20

Specification ➔ Page 16 ➔ Page 17 ➔ from Page 22 ➔ from Page 24

4/1 Model overview Logano S825L and S825L LN boilers and Logano plus SB825L and SB825L LN gas fired condensing boilers

5

Oil and gas fired special boilers 1


1.4 Features and characteristics

● Three-pass designTheLogano S825 L LN boiler and the Logano plus SB825 L LN gas fired condensing boilers achieve excellent combustion values because of three-pass technology.

● Optimised temperaturesThese boilers provide a generously dimensioned, dual-row secondary heating surface inside the second pass. Extremely low temperatures can be achieved in the front reversing area (from the second to the third pass) because no turbulators are used, and the internal hot gas reversing chamber is fully surrounded by water. This in turn leads to a significant reduction of the stress exerted on the door.

● Compact constructionThe secondary annular heating surfaces, which are symmetrically arranged around the combustion chamber, enable the boiler to be constructed with compact dimensions. This leads to low weight and space requirements. The combustion chamber door can be arranged with l.h. or r.h. opening.

● Environmentally compatible and low emissionsThe three-pass design and the water-cooled combustion chamber offer ideal pre-requisites for low emissions, in particular in connection with modern burners, which have been closely matched to the boiler design. Particularly when using oil burners, the boiler types Logano S825 L LN and Logano plus SB825 L LN with their large combustion chambers (table 4/1) are ideally suited to meet high demands for low emissions.

● EconomyDepending on fuel temperature and boiler loading, extremely high levels of efficiency can be achieved.

The radiation losses of the boiler are negligible, and the full utilisation of the burner control range enables favourable part load efficiency levels to be achieved.

● Operational reliabilityThe optimised combustion chamber design and the water guidance system make S825 L LN boilers and SB825 L LN gas fired condensing boilers extremely reliable and safe. The low water content permits rapid heating-up and an operation with a low minimum return temperature. This achieves a rapid transition through the dew point range during the heat-up phase.

● Even load distributionThe base-frame of the boiler is equipped with channel sections to provide an even load distribution. Additional boiler foundations are therefore superfluous on level floors.

● Easy maintenanceThe boiler front door can be fully swung out and can be opened even when the burner is already installed. Combustion chamber and secondary heating surfaces are freely accessible when the door is open enabling quick and simple cleaning. The reversing chamber is visible through the combustion chamber. An inspection port on the water side can be supplied as an option. This enables a representative inspection of the heating surfaces. This affords the opportunity to view the heating surface from the water chamber.

● Matching modular componentsFor all boilers, numerous matching components are offered enabling a complete, optimised system to be created.

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2


Principles

2.1 Principles of condensing technology

2.1.1 Calorific value and gross calorific value

The calorific value (net) Hi (previous designation Hu)states the heat obtainable from one cubic metre of gasor one kilogramme of fuel oil. For this reference value,the combustion products are present in a gaseous form.

The gross calorific value Hs (previous designation Ho),unlike the net calorific value Hi, also includes thecondensation heat of the water vapour as additionalenergy component.

2.1.2 Boiler efficiency above 100 %

Condensing boilers derive their description from thefact that they not only utilise the net calorific value Hi,but also the gross calorific value Hs of a given fuel.

For all efficiency calculations in German andEuropean standards the net calorific value Hi isgenerally selected as reference value at 100 %,resulting in possible boiler efficiency levels above100 %. This is the only effective way of comparingconventional boilers with condensing boilers.

Boiler efficiencies up to 15 % higher than modernboilers can be achieved. Compared with olderinstallations, energy savings of up to 40 % are feasible.

Comparing the energy utilisation of modern boilersand gas fired condensing boilers would, for example,lead to the following energy calculation (➔ 6/1):

Condensation heat (latent heat)

● For natural gas, the proportion of condensation heat amounts to 11 %, relative to the net calorific value Hi.This heat portion is not utilised in conventional boilers.

● By condensing the water vapour the gas fired condensing boiler can, to the greatest extent, utilise this potential heat.

CaptionηΚ Boiler efficiencyHi Gross calorific value

Flue gas loss (sensible heat)

● In conventional boilers flue gasses are drawn off at relatively high temperatures of approx. 150 to 210 °C, leading to the loss of unused heat of approx. 6 to 9 %.

● The dramatic reduction of the flue gas temperatures in gas fired condensing boilers utilises the sensible heat proportion within the hot gas and therefore lowers the flue gas loss.

6/1 Energy comparison between a conventional boiler and a gas fired condensing boiler

ηK = 92.5 %

11.0 % unutilised condensation heat

7.4 % flue gas losses

0.1 % radiation losses

3.0 % unutilised condensation heat

2.9 % flue gas losses

0.1 % radiation losses

Conventional boiler

Gas fired condensing boiler

111 %relative to Hi

ηK = 105 %

111 %relative to Hi

2 Principles

7

Principles 2


2.2 Optimum utilisation of condensing technology

2.2.1 Matching the technology to the heating water

Gas fired condensing boilers can be integrated into anyheating system. The useable proportion ofcondensation heat and the utilisation level resultingfrom the operating mode however, are subject to theheating system design.

The hot gas must be cooled to below its dew point tomake the condensing heat of the water vapourcontained within the hot gas useable. Therefore itfollows, that the level of utilisation of condensationheat depends on the design of the system temperaturesor the hours run in the condensation range. This isillustrated in examples 7/1 and 7/2. The dew pointtemperature is 50 °C.

Designing the return temperature of the heating system to be 30 °C

With this heating system, the performance of thecondensing technology will apply to the entire heatingperiod. The low return temperatures will always bebelow the dew point temperature, makingcondensation heat available at all times (➔ 7/1). Thisis achieved by low-temperature area heating orunderfloor heating systems, which are particularlysuited to condensing boilers.

Designing the return temperature of the heating system to be 60 °C

Even when designing for a temperature of 60 °C, anabove average utilisation of condensing heat forapprox. 95 % of the annual heating requirement isachievable. This applies to outside temperatures of –7 °C to +20 °C (➔ 7/2).

Older heating systems designed for 90/70 °C are todaypractically operated at 75/60 °C because of the safetymargins applied in the old DIN 4701 dating from1959. Even if these systems are operated attemperatures of 90/70 °C and with modulating,weather-compensated heating circuit temperatures,these will still utilise condensation heat during 80 % ofthe annual heating season.

Captiona Annual heating curveb Dew point temperature curvec Heating circuit temperaturesB Operating proportion utilising condensation heatWHa Annual heat requirementϑa Outside temperatureϑHW Heating water temperature

7/1 Utilisation of condensation heat (heating circuit designed for 40/30 °C)

7/2 Utilisation of condensation heat (heating circuit designed for 75/60 °C)

100

80

60

40

20

0

50

100

80

60

40

20

0

aB

b

c

WHa

ϑa/˚C

– 15 – 10 – 5 5 10 15 20± 0

%ϑHW

˚C

80

60

40

20

0

100

80

60

40

20

0

95

50

a

b

cWHa

ϑa/˚C

– 15 – 10 – 5 5 10 15 20± 0

%ϑHW

˚C

B

8

2


Principles

2.2.2 High standard efficiency

The examples 7/1 and 7/2 illustrate, that the differentproportion of utilisation of the condensation heatexerts a direct influence on the energy utilisation of thegas fired condensing boiler.

Gas fired condensing boilers achieve high utilisationlevels because of the following:

– High CO2 values:The higher the CO2 value, the higher the dew point temperature of the hot gases.

– Low return temperatures:The lower the return temperature, the higher the condensation rate and therefore the lower the flue gas temperature.

The Logano S825L and S825L LN as well as Loganoplus SB825L and SB825L LN boilers can be individuallymatched to each project and the given systemconditions or requirements.Your local Buderus sales office will provide you withparameters suitable for each individual project.

2.2.3 Design tips

For new installations, all opportunities should beexploited to operate a gas fired condensing boiler tooptimum effect. You will achieve high utilisation levelsif the following criteria are observed:

● Limit the return temperature upstream of the condensing heat exchanger, at least partially, to a maximum of 50 °C. In this connection it is important to note that, due to the separate connections for boiler and condensing heat exchanger, a part volume flow of 20 % with a lower design temperature (e.g. 40/30 °C) is sufficient, to achieve an excellent utilisation of the condensing principle.

● Aim for a temperature spread between flow and return of at least 20 K.

● Avoid installations for raising the return temperature (e.g. four-way mixers, bypass controls, low loss headers, zero pressure distributors and similar).

Detailed information for the hydraulic connection arecontained in chapter "System examples"(➔ Page 58 and following).

2.3 Efficiency considerations

2.3.1 Simplified comparison of conventional boilers and gas fired condensing boilers

Fuel costs

Parameters

– Gas combustion

– Building heat requirement QN = 2000 kW

– Annual heating energy demand QA = 3400000 kWh p.a.

– System design temperatures:Ventilation ϑV /ϑR = 90/70 °C (prop. 20 %)Radiators ϑV /ϑR = 75/60 °C (prop. 50 %)Underfloor heating ϑV /ϑR = 40/30 °C (prop. 30 %)

– Fuel costs KB = 0.25 E/m3

– Conventional boiler Logano S825L-2500, rated output 2500 kW, ηN = 95.2 %

– Logano plus SB825L-2500 gas fired condensing boiler, rated output 2500 kW (boiler 1840 kW, condensing heat exchanger 160 kW), ηN = 102.6 %

➔ The stated level of efficiency ηN for the Logano plusSB825L-2500 gas fired condensing boiler applies, if theunderfloor circuits are separately connected to thecondensing heat exchanger.

9

Principles 2


Calculation formulae

Annual fuel consumption

Annual fuel costs

Calculating magnitudesBV Annual fuel consumption in m3 p.a.Hi Gross calorific value, in this case natural gas simplified at

10 kWh/m3

KB Fuel costsKby Annual fuel costsQA Net heating energy requirement in kWh p.a.ηN Standard efficiency in %

Result

The heating system with the gas fired condensingboiler leads to fuel cost savings of approximatelyE 6443 p.a.

Investment costs

Investment costs are based on a complete boilersystem. This includes the costs for the boiler, the boilercontrol unit, a pressure-jet burner, the flue gas systemand the costs for all relevant safety equipment andthat for raising the return temperature. The costs forthe Logano plus SB825L gas fired condensing boileradditionally include a system for neutralising thecondensate. Installation costs have been excluded inboth cases.

Amortisation

In this example, the additional investment is recoupedin three years through reduced fuel costs. Generallyone should say, that the condensing technology paysfor itself more rapidly, the greater the rated output andtherefore the higher the absolute fuel costs are. Allcalculations exclude any possible grants. The gas firedcondensing boilers Logano plus SB825L and SB825LLN offer the possibility of integrating additionalcondensing heat exchangers. This would result inhigher efficiency levels and therefore reduced fuelcosts.

9/1 Formula for the annual fuel consumption

9/2 Formula for the annual fuel costs

Calculation resultsLogano

S825L-2500Logano plus

SB825L-2500

Fuel consumption 357150 m3 p.a. 331380 m3 p.a.

Fuel costs E 89288 p.a. E 82845 p.a.

9/3 Fuel consumption and costs of conventional boilers and gas fired condensing boilers

BVQA

ηN Hi⋅----------------=

KBa BV KB⋅=

Total investment1)

1) Incl. accessories

LoganoS825L-2500

Logano plusSB825L-2500

Total investment for the boiler system

E 50000 E 63000

9/4 Investment for a conventional boilerand a gas fired condensing boiler (figures were rounded)

Type of cost LoganoS825L-2500

Logano plusSB825L-2500

Investment costs E 50000 E 63000

Capital outlay1)

1) Annual repayments 9.44 %, interest 7 %, maintenance costs 1 %

E 5220 p.a. E 6577 p.a.

Fuel costs E 89288 p.a. E 82845 p.a.

Total costs E 94508 p.a. E 89422 p.a.

9/5 Total investment for a conventional boilerand a gas fired condensing boiler (figures were rounded)

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3


Technical description

3.1 Logano S825L and S825L LN boilers and Logano plus SB825L and SB825L LN gas fired condensing boilers

3.1.1 Equipment summary

The Logano S825L and S825L LN boilers and theLogano plus SB825L and SB825L LN condensingboilers are special dual-fuel boilers designed forpositive pressure combustion to EN 303. These boilersare designed for producing low pressure heating waterwith maximum temperatures of 110 °C (shutdowntemperature of the high limit safety cut-out) for use inheating systems which meet the requirements ofEN 12828. The permissible overall operating pressuremust not exceed 6 bar (or 10 bar). Please contact yournearest Buderus sales office, if you require higherpressures. The modular construction of boiler andancillary equipment allows almost universalapplication.

Logano S825L and S825L LN boilers andLogano plus SB825L and SB825L LN gas fired condensing boilers

● Round boiler casing made from formed aluminium plate

● Visible boiler components are primed in blue

● Thermal insulation (100 mm) and well insulated boiler door

● Boiler pressure body with connections for flow, return, safety valve and drain

● Inspection port on the water side as option

● Rear lower clean-out aperture on the flue gas collector

● Boiler plinth frame for even load distribution and easy handling

● Large boiler door with l.h. hinges (on request with r.h. hinges)

● Air-cooled combustion chamber sight glass

Logano plus SB825L and SB825L LN gas fired condensing boilers

● With integral stainless steel condensing heat exchanger with connections for flow, return and condensate drain

● Water connections either on the l.h. or r.h. side

3.1.2 Principle of operation

10/1 Cross-section with principle of operation for Logano S825L and S825L LN boilers (caption ➔ Page 11)

1 2

12 11

4 53

10

9

8

76

3 Technical description

11

Technical description 3


Boiler technology

A water guide element is integrated below the returnconnector on all Logano S825L and S825L LN boilersand Logano plus SB825L and SB825L LN gas firedcondensing boilers. Because of its velocity, the boilerreturn water creates an injection effect at this point, sothat the hotter boiler water flows towards the coolerreturn water, with which it is mixed. The well-aimedsupply of the return water leads to an excellent flowthrough the entire boiler cross-section. The wholeboiler provides an extremely even temperaturedistribution because of the flat temperature slopeinside the boiler body. This flow through the boilerleads to a dry and safe heating operation with aminimum return temperature of only 50 °C.

The boiler is constructed according to the three-passprinciple with a countercurrent heat exchanger design.Together with an effective heating surface layout,these are the prerequisites for low emissions and highenergy utilisation. The Logano S825L and S825L LNboilers achieve, subject to the individual system, veryhigh standard efficiencies, which can be increased to106 % with Logano plus SB825L and SB825L LN gasfired condensing boilers.

Gas fired condensing technology

Compared to conventional Logano S825L and S825LLN boilers, the Logano plus SB825L and SB825L LN gasfired condensing boilers are equipped with additionalstainless steel bare tube condensing heat exchangers.This exchanger is integrated into the flue gas collector.The condensing heat exchanger also follows themodular design principle. Therefore, the most suitableheat exchanger size and possibly number ofexchangers can be freely selected for each project.

Caption (➔ 10/1 to 11/1)1 Burner door2 Safety flow (➔ 82/1)3 Water guidance system4 Return (➔ 81/1 and 84/1)5 Flow (➔ 80/1)6 Hot gas reversing chamber7 Aluminium casing8 High-grade insulation without thermal bridges9 Dual-row first secondary heating surface (second pass)10 Second secondary heating surface (third pass)11 Combustion chamber (first pass)12 Blast tube13 Flow condensing heat exchanger14 Stainless steel condensing heat exchanger15 Return condensing heat exchanger16 Condensate connection17 Drain connection (➔ 88/2)18 Cleaning aperture

➔ Optional inspection port on the water side

11/1 Principles of operation of the Logano plus SB825L and SB825L LN gas fired condensing boilers

43 75 6821

13

14

16

18

15

16

17

9101112

12

3



3.2 Dimensions and specification – Logano S825L and S825L LN boilers

3.2.1 Dimensions of Logano S825L boilers, output from 1000 to 5200

Caption1 Flow safety line / safety valve2 Return3 Flow4 Flue outlet5 Flue gas condensate drain6 Boiler drain

12/1 Dimensions of Logano S825L boilers, output from 1000 to 5200 (dim. in mm)

H1

L3

L1

L2

L7 B2

B1

L4

L5

L6

95 240

80

50

H2 H3

H4

D1

1 2 3 4

5 6

Boiler output 1000 1350 1900 2500 3050 3700 4200 5200

Length L1

L2

mmmm

26802425

29502695

32202960

36753420

37253465

40753820

45704250

47004380

Height H2

H3

mmmm

16151615

17151715

18151815

18651865

19651965

20152015

21152115

22002210

Width B1 mm 1324 1424 1524 1574 1674 1724 1824 1924

Combustion chamber Length∅

mmmm

2201600

2471660

2698730

3149776

3197846

3553901

3987932

41061012

Burner door DepthH4

mmmm

190800

190850

190900

190925

190975

1901000

2571050

2571100

Base frame L7

B2

Channel section

mmmmmm

2100910120

2350910120

2560930160

30601130160

30601130160

34101150200

39201260220

39201510220

Flue outlet D1 mm ➔ 27/1

H1 mm 1180 1240 1340 1350 1415 1490 1500 1600

Flow and return flange DN ➔ 26/1

Flow safety line flange DN ➔ 26/3

Clearance L3

L4

L5

L6

mmmmmmmm

1390450600

-

1560500600

-

1710550600

-

2180550650

-

2150600650

-

2490600800

-

2870600650

-

2770800750

-

Boiler drain DN 25 32 32 32 32 32 32 32

Flue gas condensate drain R 6"" 6"" 6"" 6"" 6"" 6"" 6"" 6""

12/2 Dimensions of Logano S825L boilers, output from 1000 to 5200 (specification ➔ 16/1)

13



3.2.2 Dimensions of Logano S825L boilers, output from 6500 to 19200


13/1 Dimensions of Logano S825L boilers, output from 6500 to 19200 (dim. in mm)

H1

L3

L1

L2

L7 B2

B1

L4

L5

L6

95 240

80

50

H2 H3

H4

D1

1 2 3 4

5 6

Boiler output 6500 7700 9300 11200 12600 14700 16400 19200

Length L1

L2

mmmm

50904770

53205000

55205200

59805655

63155990

70506725

75307170

79807620

Height H2

H3

mmmm

24002410

25502560

27002710

28502900

30003025

32003270

35003570

37003770

Width B1 mm 2124 2274 2424 2574 2724 2924 3224 3424


mmmm

44851092

47141177

49131267

53621344

56611450

63301530

68281606

72661706

Burner door DepthH4

mmmm

2571200

2571275

2571350

2591425

2591500

2591600

2941750

2941850

Base frame L7

B2

Channel section

mmmmmm

42801510220

44801520240

46501610240

50501630280

53201890280

60001890280

63902100320

67902100320


H1 mm 1750 1850 2000 2100 2200 2440 2600 2750



Clearance L3

L4

L5

L6

mmmmmmmm

31308001000400

310010001100500

325010001100500

343012001100500

310018001100500

378018001100500

394020001200600

434020001200600

Boiler drain DN 50 50 50 50 50 50 50 50

Flue gas condensate drain R 6" 6" 6" 6" 6" 6" 6" 6"

13/2 Dimensions of Logano S825L boilers, output from 6500 to 19200 (specification ➔ 16/2)

14

3



3.2.3 Dimensions of Logano S825L LN boilers, output from 750 to 3500


14/1 Dimensions of Logano S825L LN boilers, output from 750 to 3500 (dim. in mm)

H1

L3

L1

L2

L7 B2

B1

L4

L5

L6

95 240

80

50

H2 H3

H4

D1

1 2 3 4

5 6

Boiler output 750 1000 1250 1500 2000 2500 3000 3500

Length L1

L2

mmmm

26802425

29502695

32202960

36753420

37253465

40753820

45704250

47004380

Height H2

H3

mmmm

16151615

17151715

18151815

18651865

19651965

20152015

21152115

22152215

Width B1 mm 1324 1424 1524 1574 1674 1724 1824 1924


mmmm

2201600

2471660

2698730

3149776

3197846

3553901

3987932

41061012

Burner door DepthH4

mmmm

190800

190850

190900

190925

190975

1901000

2571050

2571100

Base frame L7

B2

Channel section

mmmmmm

2100910120

2350910120

2560930160

30601130160

30601130160

34101150200

39201260220

39201510220


H1 mm 1180 1240 1340 1350 1415 1490 1500 1600



Clearance L3

L4

L5

L6

mmmmmmmm

1390450600

-

1560500600

-

1710550600

-

2180550650

-

2150600650

-

2490600800

-

2870600650

-

2770800750

-

Boiler drain DN 25 32 32 32 32 32 32 32

Flue gas condensate drain R 6"" 6"" 6"" 6"" 6"" 6"" 6" 6""

14/2 Dimensions of Logano S825L LN boilers, output from 750 to 3500 (specification ➔ 17/1)

15



3.2.4 Dimensions of Logano S825L LN boilers, output from 4250 to 17500


15/1 Dimensions of Logano S825L LN boilers, output from 4250 to 17500 (dim. in mm)

H1

L3

L1

L2

L7 B2

B1

L4

L5

L6

95 240

80

50

H2 H3

H4

D1

1 2 3 4

5 6

Boiler output 4250 5250 6000 8000 10000 12000 14000 17500

Length L1

L2

mmmm

50904770

53205000

55205200

59805655

63155990

70506725

75307170

79807620

Height H2

H3

mmmm

24152415

25502560

27002710

28502900

30003025

32003270

35003570

37003770

Width B1 mm 2124 2274 2424 2574 2724 2924 3224 3424


mmmm

44851092

47141177

49131267

53621344

56611450

63301530

68281606

72661706

Burner door DepthH4

mmmm

2571200

2571275

2571350

2591425

2591500

2591600

2941750

2941850

Base frame L7

B2

Channel section

mmmmmm

42801510220

44801520240

46501610240

50501630280

53201890280

60001890280

63902100320

67902100320


H1 mm 1750 1850 2000 2100 2200 2440 2600 2750



Clearance L3

L4

L5

L6

mmmmmmmm

31308001000

-

310010001100

-

325010001100500

343012001100500

310018001100500

378018001100500

394020001200600

434020001200600

Boiler drain DN 50 50 50 50 50 50 50 50


15/2 Dimensions of Logano S825L LN boilers, output from 4250 to 17500 (specification ➔ 17/2)

16

3



3.2.5 Specification of Logano S825L boilers, output from 1000 to 5200

3.2.6 Specification of Logano S825L boilers, output from 6500 to 19200

Boiler output 1000 1350 1900 2500 3050 3700 4200 5200


Despatch weight 6 bar10 bar

tt

2.32.4

2.93.1

3.53.7

4.65.0

5.05.4

5.76.5

7.38.0

8.39.2

Total weight in use1)

1) The total weight in use comprises the boiler weight plus the weight of the burner, the control unit, fittings and the boiler pipework.

6 bar10 bar

tt

3.63.7

4.64.8

5.55.7

6.87.2

7.78.1

8.89.5

11.111.8

12.613.5

Boiler water content m3 1.3 1.7 2.0 2.2 2.7 3.0 3.8 4.3

Combustion chamber volume

m3 1.09 1.40 1.98 2.58 3.05 3.67 4.61 5.44

Flue gas temperature °C ➔ 37/2

Draught (required draught) Pa 0

Hot gas pressure drop mbar ➔ 30/1

Permiss. flow temperature2)

2) Upper limit of the high limit safety cut-out (STB); max. possible operating flow temperature (➔ 61/3).

°C 110

Permiss. operating pressure

bar 6 or 103)

3) Higher pressures on request.

CE designation CE 0085 BO 0396

16/1 Specification of Logano S825L boilers, output from 1000 to 5200 (dim. ➔ 12/1)

Boiler output 6500 7700 9300 11200 12600 14700 16400 19200



tt

10.211.7

12.414.1

14.816.9

17.819.9

20.222.8

25.728.1

32.335.8

37.839.8



6 bar10 bar

tt

16.217.7

19.72)

21.42)

2) Excluding the weight for burner and pipework.

23.62)

25.72)28.72)

30.82)32.92)

35.52)42.52)

44.52)55.32)

58.82)65.72)

67.72)



m3 7.13 8.91 10.55 13.04 15.62 20.41 25.27 31.76


Draught (required draughtrequired draught)

Pa 0




°C 110


bar 6 or 104)



16/2 Specification of Logano S825L boilers, output from 6500 to 19200 (dim. ➔ 13/1)

17



3.2.7 Specification of Logano S825L LN boilers, output from 750 to 3500

3.2.8 Specification of Logano S825L LN boilers, output from 4250 to 17500

Boiler output 750 1000 1250 1500 2000 2500 3000 3500



tt

2.22.3

2.82.9

3.33.4

4.24.5

4.75.1

5.36.1

6.97.6

7.78.6



6 bar10 bar

tt

3.63.7

4.64.7

5.45.5

6.77.0

7.68.0

8.69.3

11.011.7

12.413.3



m3 1.40 1.40 1.98 2.58 3.05 3.67 4.61 5.44






°C 110


bar 6 or 103)



17/1 Specification of Logano S825L LN boilers, output from 750 to 3500 (dim. ➔ 14/1).

Boiler output 4250 5250 6000 8000 10000 12000 14000 17500



tt

9.310.8

11.413.0

13.415.7

16.518.6

19.321.9

24.727.0

30.834.4

36.738.8



6 bar10 bar

tt

16.017.5

19.52)

21.12)


23.22)

25.52)28.52)

30.62)32.82)

35.42)42.22)

44.52)55.12)

58.72)65.62)

67.72)



m3 7.13 8.91 10.55 13.04 15.62 20.41 25.27 31.76






°C 110


bar 6 or 104)



17/2 Specification of Logano S825L LN boilers, output from 4250 to 17500 (dim. ➔ 15/1)

18

3



3.3 Dimensions and specification for Logano plus SB825L and SB825L LN gas fired condensing boilers

3.3.1 Dimensions of Logano plus SB825L boilers, output from 1000 to 5200

Caption1 Flow safety line2 Return3 Flow4 Return CHE (RHE)

5 Flow CHE (RHE)6 Flue outlet7 Condensate drain CHE (AKO)8 Flue gas condensate drain9 Boiler drain

18/1 Dimensions of Logano plus SB825L gas fired condensing boilers, output from 1000 to 5200 (dim. in mm)

H1

L3

L1

L2

L7 B2

B1

L4

L5

L6

95 240

80

690

510

150

H2 H3

8 9

7

1 2 3

H6

H5

4 65B4

B3

H4

1)

1) CHE connections (optionally on r.h. side)

Boiler output 1000 1350 1900 2500 3050 3700 4200 5200

Length L11)

L2

1) Standard version with one condensing heat exchanger (CHE); for additional CHE, length L1 increases by 300 mm respectively.

mmmm

33702425

36402695

39102960

43653420

44153465

47653820

52604250

53904380

Height H2

H3

mmmm

16151615

17151715

18151815

18651865

19651965

20152015

21152115

22002210

Width B1 mm 1324 1424 1524 1574 1674 1724 1824 1924


mmmm

2201600

2471660

2698730

3149776

3197846

3553901

3987932

41061012

Burner door DepthH6

mmmm

190800

190850

190900

190925

190975

1901000

2571050

2571100

Base frame L7

B2Channel section

mmmmmm

2100910120

2350910120

2560930160

30601130160

30601130160

34101150200

39201260220

39201510220

CHE H1

H4

H5

B3

B4

mmmmmmmmmm

10602515951004580

1050326670

1094625

11503266951154655

12054017701254705

1215422820

1344725

12404478451384745

12604978951454780

13305729701564835

Flange - CHE flow/return (VHE/RHE) DN ➔ 27/2

Condensate drain CHE (AKO) DN ➔ 27/2

Flue outlet DN ➔ 27/1



Clearance L3

L4

L5

L6

mmmmmmmm

1390450600

-

1560500600

-

1710550600

-

2180550650

-

2150600650

-

2490600800

-

2870600650

-

2770800750

-

Boiler drain DN 25 32 32 32 32 32 32 32

Flue gas condensate drain R 6"" 6"" 6"" 6"" 6"" 6"" 6"" 6""

18/2 Dimensions of Logano plus SB825L gas fired condensing boilers, output from 1000 to 5200 (specification ➔ 16/1)

19



3.3.2 Dimensions of Logano plus SB825L boilers, output from 6500 to 19200


5 Flow CHE (VHE)6 Flue outlet7 Condensate drain CHE (AKO)8 Flue gas condensate drain9 Boiler drain

19/1 Dimensions of Logano plus SB825L gas fired condensing boilers, output from 6500 to 19200 (dim. in mm)

H1

L3

L1

L2

L7 B2

B1

L4

L5

L6

95 240

80

690

510

150

H2 H3

8 9

7

1 2 3

H6

H5

4 65B4

B3

H4

1)


Boiler output 6500 7700 9300 11200 12600 14700 16400 19200

Length L11)

L2

mmmm

57804770

60105000

62105200

66705655

70055990

77406725

82207170

86707620

Height H2

H3

mmmm

24002410

25502560

27002710

28502900

30003025

32003270

35003570

37003770

Width B1 mm 2124 2274 2424 2574 2724 2924 3224 3424


mmmm

44851092

47141177

49131267

53621344

56611450

63301530

68281606

72661706

Burner door DepthH6

mmmm

2571200

2571275

2571350

2591425

2591500

2591600

2941750

2941850

Base frame L7

B2

Channel section

mmmmmm

42801510220

44801520240

46501610240

50501630280

53201890280

60001890280

63902100320

67902100320

CHE H1

H4

H5

B3

B4

mmmmmmmmmm

136069710951754930

1495797

11951804955

1550872127020041055

1705897129520541080

1750997

139522041155

19001097149523541230

20301197159525041305

21501297169526541380






Clearance L3

L4

L5

L6

mmmmmmmm

31308001000400

310010001100500

325010001100500

343012001100500

310018001100500

378018001100500

394020001200600

434020001200600

Boiler drain DN 50 50 50 50 50 50 50 50


19/2 Dimensions of Logano plus SB825L gas fired condensing boilers, output from 6500 to 19200 (specification ➔ 16/2)1) Standard version with one condensing heat exchanger (CHE); for additional CHE, length L1 increases by 300 mm respectively.

20

3



3.3.3 Dimensions of Logano plus SB825L LN boilers, output from 750 to 3500



20/1 Dimensions of Logano plus SB825L LN gas fired condensing boilers, output from 750 to 3500 (dim. in mm)

H1

L3

L1

L2

L7 B2

B1

L4

L5

L6

95 240

80

690

510

150

H2 H3

8 9

7

1 2 3

H6

H5

4 65B4

B3

H4

1)


Boiler output 750 1000 1250 1500 2000 2500 3000 3500

Length L11)

L2


mmmm

33702425

36402695

39102960

43653420

44153465

47653820

52604250

53904380

Height H2

H3

mmmm

16151615

17151715

18151815

18651865

19651965

20152015

21152115

22152215

Width B1 mm 1324 1424 1524 1574 1674 1724 1824 1924


mmmm

2201600

2471660

2698730

3149776

3197846

3553901

3987932

41061012

Burner door DepthH6

mmmm

190800

190850

190900

190925

190975

1901000

2571050

2571100

Base frame L7

B2

Channel section

mmmmmm

2100910120

2350910120

2560930160

30601130160

30601130160

34101150200

39201260220

39201510220

CHE H1

H4

H5

B3

B4

mmmmmmmmmm

1060227545914535

1050251595

1004580

11502515951004580

12053266701094625

1215326695

1154655

12404017701254705

12604228201344725

13304478451384745






Clearance L3

L4

L5

L6

mmmmmmmm

1390450600

-

1560500600

-

1710550600

-

2180550650

-

2150600650

-

2490600800

-

2870600650

-

2770800750

-

Boiler drain DN 25 32 32 32 32 32 32 32


20/2 Dimensions of Logano plus SB825L LN gas fired condensing boilers, output from 750 to 3500 (specification ➔ 17/1)

21



3.3.4 Dimensions of Logano plus SB825L LN boilers, output from 4250 to 17500



21/1 Dimensions of Logano plus SB825L LN gas fired condensing boilers, output from 4250 to 17500 (dim. in mm)

H1

L3

L1

L2

L7 B2

B1

L4

L5

L6

95 240

80

690

510

150

H2 H3

8 9

7

1 2 3

H6

H5

4 65B4

B3

H4

1)


Boiler output 4250 5250 6000 8000 10000 12000 14000 17500

Length L11)

L2


mmmm

57804770

60105000

62105200

66705655

70055990

77406725

82207170

86707620

Height H2

H3

mmmm

24152415

25502560

27002710

28502900

30003025

32003270

35003570

37003770

Width B1 mm 2124 2274 2424 2574 2724 2924 3224 3424


mmmm

44851092

47141177

49131267

53621344

56611450

63301530

68281606

72661706

Burner door DepthH6

mmmm

2571200

2571275

2571350

2591425

2591500

2591600

2941750

2941850

Base frame L7

B2

Channel section

mmmmmm

42801510220

44801520240

46501610240

50501630280

53201890280

60001890280

63902100320

67902100320

CHE H1

H4

H5

B3

B4

mmmmmmmmmm

13604978951454780

1495572970

1564835

155069710951754930

170579711951804955

1750872

127020041055

1900897129520541080

2030997139522041155

21501197159525041305






Clearance L3

L4

L5

L6

mmmmmmmm

31308001000

-

310010001100

-

325010001100500

343012001100500

310018001100500

378018001100500

394020001200600

434020001200600

Boiler drain DN 50 50 50 50 50 50 50 50


21/2 Dimensions of Logano plus SB825L LN gas fired condensing boilers, output from 4250 to 17500 (specification ➔ 17/2)

22

3



3.3.5 Dimensions of Logano plus SB825L, output from 1000 to 5200

➔ Alternative condensing heat exchanger matches and sizing on request.

Boiler output 1000 1350 1900 2500 3050 3700 4200 5200

Max. rated boiler output kW 1000 1350 1900 2500 3050 3700 4200 5200

Rated output CHE

at 30 °C1)

at 60 °C1)

1) Water inlet temperature into the condensing heat exchanger (CHE).

kWkW

9036

11142

15661

21285

254101

281104

326125

413162


tt

2.52.6

3.13.3

3.84.0

4.95.3

5.35.7

6.06.8

7.78.4

8.79.6



6 bar10 bar

tt

3.83.9

4.95.1

5.86.0

7.17.5

8.18.5

9.29.9

11.512.2

13.114.0



m3 1.24 1.61 2.21 2.93 3.36 4.08 5.01 5.94

Flue gas temperature3)

3) Based on the maximum boiler load; alternative boiler loads ➔ 38/2; reference temperatures 80/60/25 °C.

at 30 °C1)

at 60 °C1)°C°C

106121

99112

107120

109124

111125

106119

108121

110124

Draught (required draught) Pa 0 (50)4)

4) The available pressure depends on the burner.

Volume flow through the CHE5)

5) Numerical value for calculating the output of the condensing heat exchanger.

mN3/h 43 58 81.7 107.5 132 159 151 156

Pressure drop on the primary side of the CHE

mbar 250 150 200 250 250 250 250 250




°C 110


bar 6 or 107)



22/1 Specification of Logano plus SB825L gas fired condensing boilers, output from 1000 to 5200 (dimensions➔ 18/1)

23



3.3.6 Dimensions of Logano plus SB825L, output from 6500 to 19200

➔ Alternative condensing heat exchanger matches and sizes on request.

Boiler output 6500 7700 9300 11200 12600 14700 16400 19200


Rated output CHE

at 30 °C1)

at 60 °C1)


kWkW

522207

619250

729284

847343

918345

1057402

1115404

1376528


tt

10.712.2

12.914.6

5.417.5

18.420.5

20.923.5

26.528.9

33.236.7

38.840.8



6 bar10 bar

tt

16.818.3

20.33)

22.03)


24.33)

26.33)29.53)

31.63)33.83)

36.43)43.53)

45.53)56.43)

59.93)66.93)

68.93)



m3 7.77 9.60 11.48 14.10 17.18 22.23 27.64 34.46



at 30 °C1)

at 60 °C1)°C°C

109123

111125

107121

112126

105118

105118

100112

105117





mN3/h 140 150 160 145 162 158 141 165


mbar 200 200 200 200 250 200 200 250




°C 110


bar 6 or 108)



23/1 Specification of Logano plus SB825L gas fired condensing boilers, output from 6500 to 19200 (dimensions➔ 19/1)

24

3



3.3.7 Dimensions of Logano plus SB825L LN, output from 750 to 3500


Boiler output 750 1000 1250 1500 2000 2500 3000 3500


Rated output CHE

at 30 °C1)

at 60 °C1)


kWkW

63.523.2

82.929.7

108.841.6

130.550.2

175.768.6

20775

254.696.1

295110.4


tt

2.42.5

3.03.1

3.53.7

4.44.7

5.05.4

5.66.4

7.27.9

8.08.9



6 bar10 bar

tt

3.83.9

4.84.9

5.65.7

7.07.3

7.98.3

8.99.6

11.412.1

12.813.7



m3 1.24 1.61 2.21 2.93 3.36 4.08 5.01 5.94



at 30 °C1)

at 60 °C1)°C°C

99115

96111

108123

104119

110125

101116

106120

107121





mN3/h 32.4 43.2 54 64.8 86.4 108 130 151


mbar 265 250 391 186 220 191 183 177




°C 110


bar 6 or 107)



24/1 Specification of Logano plus SB825L LN gas fired condensing boilers, output from 750 to 3500 (dimensions➔ 20/1)

25



3.3.8 Dimensions of Logano plus SB825L LN, output from 4250 to 17500


Boiler output 4250 5250 6000 8000 10000 12000 14000 17500


Rated output CHE

at 30 °C1)

at 60 °C1)


kWkW

351129

442170

499189

658254

784293

957379

1023369

1339544


tt

9.711.2

11.813.4

13.916.2

17.019.1

19.922.5

25.327.6

31.535.1

37.639.7



6 bar10 bar

tt

16.417.9

20.03)

21.63)


23.83)

26.13)29.13)

31.23)33.53)

36.13)43.03)

45.33)56.03)

59.63)66.73)

68.83)



m3 7.77 9.60 11.48 14.10 17.18 22.23 27.64 34.46



at 30 °C1)

at 60 °C1)°C°C

106121

110124

102117

107122

105119

112126

103116

108122





mN3/h 160 160 160 160 160 161 161 161


mbar 198 198 198 198 198 200 200 200




°C 110


bar 6 or 108)



25/1 Specification of Logano plus SB825L LN gas fired condensing boilers, output from 4250 to 17500 (dimensions➔ 21/1)

26

3



3.4 Variable connections for all models subject to the rated output

3.4.1 Flow and return connections for all models

3.4.2 Connections of the flow safety line or the safety valve

For design spread and rated output in kW Recom. internal

diameter1)

1) Flange connections as PN 16 to DIN 2633; the stated internal diameters are suggestions and can be individually determined.

ΔT = 15 K ΔT = 20 K ΔT = 30 K ΔT = 40 K DN

> 175≤ 275

> 235≤ 367

> 352≤ 550

> 470≤ 734

50

> 275≤ 465

> 367≤ 620

> 550≤ 931

> 734≤ 1241

65

> 465≤ 705

> 620≤ 940

> 931≤ 1410

> 1241≤ 1881

80

> 705≤ 1102

> 940≤ 1469

> 1410≤ 2204

> 1881≤ 2938

100

> 1102≤ 1722

> 1469≤ 2296

> 2204≤ 3444

> 2938≤ 4592

125

> 1722≤ 2479

> 2296≤ 3306

> 3444≤ 4959

> 4592≤ 6612

150

> 2479≤ 4408

> 3306≤ 5877

> 4959≤ 8816

> 6612≤ 11755

200

> 4408≤ 6887

> 5877≤ 9183

> 8816≤ 13775

> 11755≤ 18367

250

> 6887≤ 9918

> 9183≤ 13224

> 13775≤ 19200

> 18367≤ 19200

300

> 9918≤ 13500

> 13224≤ 18000

– – 350

> 13500≤ 17633

> 18000≤ 19200

– – 400

26/1 Flow and return connectors for Logano S825L and S825L LN boilers plus Logano plus SB825L and SB825L LN gas fired condensing boilers subject to design spread and rated output.

Logano S825L

Logano plus SB825L

Logano S825L LN

Logano plusSB825L LN

Max. internal diameter for flow and return connections

Boiler output

Boiler output

DN

1000 750 100

13501000

to 1500125

1900 2000 150

2500to 4200

2500to 4250

200

5200to 7700

5250to 6000

250

9300to 12600

8000to 12000

300

14700to 16400

14000 350

19200 17500 400

26/2 Maximum possible internal diameters for flow and return connectors for Logano S825L and S825L LN boilers and Logano plus SB825L and SB825L LN gas fired condensing boilers subject to boiler output; larger internal diameters on request.

Maximumresponse pressure

Max. boiler output with a safety valve supplied by ARI, Fig. 903with an internal diameter of the flow safety line of1)

1) Multiple connections for flow safety line on request.

DN 20 DN 25 DN 32 DN 40 DN 50 DN 65 DN 80 DN 100 DN 125 DN 150

bar kW kW kW kW kW kW kW kW kW kW

2.5 217 340 565 870 1360 2300 3480 5440 7120 9900

3.0 250 391 649 1000 1560 2640 4000 6250 8190 11400

4.0 312 488 810 1250 1950 3300 5000 7800 10200 14200

5.0 370 578 960 1480 2310 3900 5910 9240 12100 16900

6.0 426 666 1100 1700 2660 4500 6820 10600 14000 19400

8.0 536 837 1390 2140 3350 5660 8580 13400 17600 24500

10.0 643 1000 1670 2570 4010 6790 10300 16000 21100 29300

26/3 Connections of the flow safety line for Logano S825L and S825L LN boilers and Logano plus SB825L and SB825L LN gas fired condensing boilers

27



3.4.3 Connections of the flue outlet for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

3.4.4 Connections of the condensing heat exchanger for the Logano plus SB825L and SB825L LN gas fired condensing boilers

Rated outputkW

Internal diameter of the flue outlet1) D1 DN

1) Dimensions to EN 12220.

Flue outlet D1 (external)mm

> 827 ≤ 1290 250 254

> 1291 ≤ 2050 315 320

> 2051 ≤ 3307 400 402

> 3308 ≤ 5167 500 505

> 5168 ≤ 8203 630 636

> 8204 ≤ 13227 800 799

> 13228 ≤ 19200 1000 1005

27/1 Connections of the flue outlet for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers subject to the rated output

Logano plusSB825L

Connection of the condensing heat exchanger (CHE)

Flow/return Condensate drain

VHE/RHE AKO

Boiler output

DN R

1000 100 1"

1350 100 1"

1900 125 1"

2500 125 1"

3050 150 1"

3700 150 1"

4200 150 1"

5200 150 1"

6500 150 1"

7700 150 1"

9300 150 15"

11200 150 15"

12600 150 15"

14700 150 15"

16400 150 15"

19200 150 15"

27/2 Variable connections of the Logano plus SB825L gas fired condensing boilers subject to the rated output


Connection of the condensing heat exchanger (CHE)

Flow/return Condensate drain

VHE/RHE AKO

Boiler output

DN R

750 80 1"

1000 100 1"

1250 100 1"

1500 100 1"

2000 125 1"

2500 125 1"

3000 150 1"

3500 150 1"

4250 150 1"

5250 150 1"

6000 150 1"

8000 150 1"

10000 150 15"

12000 150 15"

14000 150 15"

17500 150 15"

27/3 Variable connections of Logano plus SB825L LN the gas fired condensing boilers subject to the rated output

28

3



3.4.5 Connections

All Logano S825L and S825L LN boilers and Logano plusSB825L and SB825L LN gas fired condensing boilers arefactory-fitted with matching flow and return

connectors. These provide the option of connectingtemperature sensors and thermostats.

CaptionN1 R5", 120 mm long (for connectors DN 32-150)

R5", 60 mm long (for connectors DN 200-400)N2 R5", 60 mm long (for connectors DN 65-80)

R5", 75 mm long (for connectors DN 32-50)R5", 40 mm long (for connectors DN 100-400)

N3 R6", 75 mm long (for connectors DN 32-150)R6", 50 mm long (for connectors DN 200-400)

28/1 Connectors for Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers with test ports for safety equipment (dim. in mm; internal diameters ➔ 26/1, 27/2 and 27/3)

250

N1

N2

N1

N2

250

N3

Return connector Flow connector

29



3.5 Boiler parameters

3.5.1 Pressure drop (primary side)

The pressure drop (primary side) is the pressuredifferential between the boiler flow and the returnconnections. It is subject to the boiler output (or theinternal diameter of the connectors) and the heatingwater flow rate. Fig. 29/1 shows the pressure dropvalues on the water side for the Logano S825L andS825L LN boilers and Logano plus SB825L and SB825LLN gas fired condensing boilers. The pressure dropvalues on the water side of the condensing heatexchangers of the Logano plus SB825L and SB825L LNgas fired condensing boilers are shown in tables 22/1 to25/1.

CaptionΔpH Pressure drop (primary side)VH Heating water volume flow

29/1 Pressure drop on the primary side of the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers; (for the pressure drop of the condensing heat exchanger, see tables 22/1 to 25/1; for the internal diameters of the flow and return connectors, see tables 26/1 and 26/2).

200

100

40

50

20

30

105 10 10050 1000

ΔpH

mbar

VH / m3

h

500

DN40

DN65

DN100

DN150

DN250

DN350

DN50

DN80

DN125

DN200

DN300

DN400

30

3



3.5.2 Hot gas pressure drop

Logano S825L

Logano S825L LN

CaptionQK Rated outputΔpG Hot gas pressure drop

30/1 Hot gas pressure drop for the Logano S825L boilers

ΔpG

mbar

18

16

14

12

10

8

6

4

2

00 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000

QK /kW

1000 13

5019

0025

0030

5037

00

4200

5200

6500

7700

9300

1120

0

1260

0

1470

0

1640

0

19200

30/2 Hot gas pressure drop for the Logano S825L LN boilers

ΔpG

mbar

18

16

14

12

10

8

6

4

2

00 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000

QK /kW

750/

1000

1250

1500

2500

2000 30

0035

00

5250

6000 80

00

1000

0

12000

1400017500

4250

31



Logano plus SB825L

Logano plus SB825L LN

CaptionQK Rated outputΔpG Hot gas pressure drop

31/1 Hot gas pressure drop of the Logano plus SB825L gas fired condensing boilers

ΔpG

mbar

18

16

14

12

10

8

6

4

2

00 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000

QK /kW

1000 13

5019

0025

0030

5037

00

4200

5200

6500

7700

9300 11

200

1260

0

1470

0

1640

0

19200

31/2 Hot gas pressure drop of the Logano plus SB825L LN gas fired condensing boilers

ΔpG

mbar

18

16

14

12

10

8

6

4

2

00 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000

QK /kW

750

1000 12

50 2000

1500

2500

4250

5250

6000

8000

1000

0

1200

0

1400

0

1750

0

3500

3000

32

3



3.5.3 Combustion chamber volume load

Some burner manufacturers quote a maximumcombustion chamber volume load to guaranteeemission values. Using diagrams 32/1 and 33/1, asuitable boiler output for the Logano S825L and S825L

LN boilers and the Logano plus SB825L and SB825L LNgas fired condensing boilers can be selected for a givencombustion chamber volume load.

Logano S825L and Logano plus SB825L

CaptionFVB Combustion chamber volume loadQK Rated output

32/1 Combustion chamber volume load for Logano S825L boilers and the Logano plus SB825L gas fired condensing boilers, subject to the rated boiler output

FVB MW/m3

2.0

1.9

1.7

1.5

1.3

1.10 2000 4000 6000 8000 10000 14000 1600012000 18000 20000

QK/kW

1000

1350

1900

2500

3050

3700

4200

5200

6500

7700

9300

1120

0

1260

0

1470

0

1640

0

19200

33



Logano S825L LN and Logano plus SB825L LN

CaptionFVB Combustion chamber volume loadQK Rated output

33/1 Combustion chamber volume load for the Logano S825L LN boilers and the Logano plus SB825L LN gas fired condensing boilers, subject to the rated boiler output

0 2000 4000 6000 8000 10000 14000 1600012000 18000 20000

FVB MW/m3

1.4

1.3

1.2

1.1

1.0

0.9

0.8

750

1000

1250

1500

2000

2500

3000

4250

3500

5250

6000

8000

1200

0

1400

0

1750

0

1000

0

34

3



3.5.4 Boiler efficiency and standby losses

The boiler efficiency indicates the relationship betweenthe rated boiler output and the rated combustionoutput subject to the boiler load and the systemtemperature. The boiler efficiency in Fig. 34/1 is, acc. toEN 303, based on a system temperature of 80/60 °C(see also figs. 37/2 and 38/1).

The standby loss is that part of the rated combustionoutput, which is required to maintain the set boilerwater temperature. Cause of this loss is the cooling ofthe boiler resulting from radiation and convectionduring the standby period (burner idle time).

Caption (➔ 34/1 to 34/3)a Partial load 60 %b Full load 100 %ϑR Return temperatureϑK Mean boiler water temperatureϕK Relative boiler loadηK Boiler efficiency

Logano S825L and S825L LN

Logano plus SB825L and SB825L LN Logano S825L and S825L LN

34/1 Efficiency of the Logano S825L and S825L LN boilers subject to boiler load (mean value for this series); system temperature 80/60 °C

ηK

%

ϕK/%

100

99

98

97

96

95

94

93

92

91

9020 30 40 50 60 70 80 90 100

S825L LN

S825L

34/2 Boiler efficiency for Logano plus SB825L and SB825L LN gas fired condensing boilers subject to the return temperature (mean values for this series with a heat exchanger tube bundle)

ηK

%

ϑR /˚C

105

104

103

102

101

100

99

98

97

96

9520 30 40 50 60 70

a

b

34/3 Boiler efficiency for the Logano S825L and S825L LN boilers subject to the mean boiler water temperature (mean values for this series)

95

94

93

92

91

9060 70 80 90 100 110

ϑK /˚C

ηK

%S825 L (LN)

S825 L

35



Boiler efficiency and standard efficiency for the Logano S825L and S825L LN

Standby losses of the Logano S825L and S825L LN and Logano plus SB825L and SB825L LN

Boiler type Boiler output

Boiler efficiency1) 2)

1) Based on a system temperature of 80/60 °C. For alternative system temperatures, the boiler efficiency alters in accordance with diagram➔ 34/3.

2) Based on the maximum rated output; for reduced output ratings, the efficiency increases in accordance with diagram➔ 34/1.

Standard efficiency1) 2)

ηK ηN

Logano S825L

1000 91.8 94.6

1350 92.9 95.3

1900 91.4 94.4

2500 91.8 94.6

3050 91.4 94.4

3700 92.4 95.0

4200 92.2 94.9

5200 91.9 94.7

6500 91.9 94.7

7700 91.9 94.8

9300 92.2 94.9

11200 92.1 94.9

12600 92.7 95.2

14700 92.7 95.2

16400 93.3 95.6

19200 92.7 95.2

Logano S825L LN

750 93.0 95.3

1000 93.3 95.5

1250 92.5 95.0

1500 92.7 95.1

2000 92.4 95.1

2500 93.1 95.4

3000 92.8 95.2

3500 92.7 95.2

4250 92.9 95.3

5250 92.6 95.1

6000 92.9 95.4

8000 92.7 95.2

10000 93.1 95.5

12000 92.6 95.1

14000 93.5 95.7

17500 92.8 95.3

35/1 Boiler efficiency levels and standard efficiency for Logano S825L and S825L LN boilers

Boiler type Boiler output

Standby lossqB

1)

1) Relative to a system temperature of 80/60 °C.

kW %2)

2) Based on the max. rated output.

Logano S825L

Logano plus SB825L

1000 1.23 0.123

1350 1.43 0.106

1900 1.64 0.086

2500 1.82 0.073

3050 2.04 0.067

3700 2.18 0.059

4200 2.46 0.059

5200 2.69 0.052

6500 3.33 0.051

7700 3.87 0.050

9300 3.98 0.043

11200 4.83 0.043

12600 5.36 0.043

14700 6.15 0.042

16400 7.37 0.045

19200 8.23 0.043

Logano S825L LN


750 1.04 0.139

1000 1.14 0.114

1250 1.24 0.099

1500 1.36 0.091

2000 1.56 0.078

2500 1.68 0.067

3000 1.88 0.063

3500 2.10 0.060

4250 2.40 0.056

5250 2.82 0.054

6000 3.04 0.051

8000 3.86 0.048

10000 4.60 0.046

12000 5.42 0.045

14000 7.20 0.051

17500 7.52 0.043

35/2 Standby losses of the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

36

3



3.5.5 Rated output of the condensing heat exchanger

All following details regarding the condensing heatexchanger (CHE) of the Logano plus SB825L andSB825L LN gas fired condensing boilers refer to theversion with one tube bundle element. Specification forthe version with two tube bundle elements on requestfrom your nearest Buderus sales office.

The rated output of the condensing heat exchangercan be calculated approximately.

Calculation formula

Calculating sizesfϕK Conversion factor acc. to diagram 36/2fϑR Conversion factor acc. to diagram 36/3QCHE,30 Rated output of the condensing heat exchanger (CHE)

at a water inlet temperature of 30 °C (➔ 22/1 to 25/1)QCHE,real Actual output (CHE)

Example

Parameters

– Boiler type Gas fired condensing boiler Logano plus SB825L

– Boiler output 2500 kW

– Rated output QK = 2300 kW

– Boiler load ϕK = 2300 kW/2500 kWϕK = 92 %

– Water inlet temperatureinto the CHE ϑCHE = 40 °C

Measure

– Conversion factor fϕK = 0.9 (➔ 36/2)fϑR = 0.825 (➔ 36/3)

– Rated output of the CHEat 30 °C (➔ 22/1) QCHE, 30 = 212 kW

Result

– Rated output of the CHE acc. to formula 36/1:QCHE, real ≈ 0.9 ⋅ 0.825 ⋅ 212 kWQCHE, real ≈ 157 kW

– Total rated outputQ ≈ (2300 + 157) kWQ ≈ 2457 kW

36/1 Approximation formula for the rated output of the condensing heat exchanger

QCHE,real fϑR fϕK QCHE,30⋅ ⋅≈

36/2 Conversion factor for calculating the rated output of the condensing heat exchanger (based on a water inlet temperature of 30 °C)

36/3 Conversion factor for calculating the rated output for alternative inlet temperatures

50 60 70 80 92 100

0.50

0.9

1.0

0.10

0.20

0.30

0.40

0.60

0.70

0.80

30 40 50 60 70

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.825

0.90

1.00

CHE

37



3.5.6 Flue gas temperature

The flue gas temperature is the temperature measuredinside the flue pipe, i.e. at the boiler flue outlet. It issubject to the boiler load and the system temperature(➔ 37/2, 38/1 and 38/2). Generally use the lowestpossible flue gas temperature to size the chimney. It isapprox. 7.5 K lower than the stated flue gastemperature, relative to the mean boiler temperatureof 70 °C.

Changing the flue gas temperature

The flue gas temperature depends on the mean boilerwater temperature. The flue gas temperatures shownin diagrams 37/2, 38/1 and 38/2 are, according toEN 303, based on a temperature pairing of 80/60 °C,i.e. the mean boiler water temperature is 70 °C. Forconversion to other temperature pairings, see 37/1.

Example

Parameters

– Boiler output 6500


– System temperatures 100/80 °C

Measure

– Changing the flue gas temperature 15 K (➔ 37/1)

– Actual flue gastemperature ϑA = 198 °C (➔ 37/2)

Result

– Flue gas temperature at full boiler load = 198 °C + 15 K = 213 °C

CaptionϑA Flue gas temperatureϕK Boiler loadηK Boiler efficiencyQK Rated output

Logano S825L

Meanboiler water temperature

Changing the flue gas temperature

°C K

60 –7.5

70 0

80 7.5

90 15

100 22.5

37/1 Changing the flue gas temperature subject to the mean boiler water temperature

37/2 Flue gas temperatures for the Logano S825L boilers subject to boiler load

230

220

210

200

190

180

170

160

90.7

91.1

91.5

92.0

92.4

92.9

93.3

93.70 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000

%

QK/kW

1000

1350

1900

2500

3050

3700

4200

5200 65

00

7700

9300

12600

1120

0

16400

14700

19200

38

3



Logano S825L LN

Caption (➔ 38/1 and 38/2)a Water inlet temperature into the condensing

heat exchanger 30 °Cb Water inlet temperature into the condensing

heat exchanger 60 °CϑA Flue gas temperatureϕK Boiler loadηK Boiler efficiencyQK Rated output

Logano plus SB825L and SB825L LN

38/1 Flue gas temperatures for the Logano S825L LN boilers subject to boiler load

220

210

200

190

180

170

160

1500 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000

QK/kW

91.1

91.5

92.0

92.4

92.9

93.3

93.7

94.1

%750

1000

/125

015

0020

0025

0030

0035

0042

50

5250

6000

8000

1000

0

12000

14000

17500

38/2 Flue gas temperatures of the Logano plus SB825L and SB825L LN gas fired condensing boilers subject to boiler load and the water inlet temperature into the condensing heat exchanger (mean value for this series)

ϕK/%

150

140

130

120

110

100

90

80

70

60

5025 50 75 100

a

b

39

Burner 4


4.1 General requirements

The Logano S825L and S825L LN boilers and theLogano plus SB825L and SB825L LN gas firedcondensing boilers can be operated with all approvedpressure-jet oil and gas burners. The pressure-jet oilburners must be type-tested in accordance with therequirements of DIN EN 267, and the pressure-jet gasburners in accordance with DIN EN 676. Please

observe all requirements for oil and gas combustionsystems as well as all locally applicable standards andregulations.

Check when combining boiler and burner, whether therequirements of the burner manufacturer regardingthe combustion chamber geometry have been met.

4.2 Tips regarding the burner selection

The burner must be able to overcome the flue gasresistance of the boiler (➔ 30/1 to 31/2) reliably. In caseof gas fired systems ensure that the pressure suppliedby the gas mains is adequate for the selected burner.

State the required burner type when ordering a LoganoS825L and S825L LN boiler or a Logano plus SB825Land SB825L LN gas fired condensing boiler. The burnerfixing equipment and the door lining are factory-prepared for each individual burner.

Fill the gap between the door lining and the blast tubewith fire-resistant flexible material.

The burner door must be able to be freely opened andpivoted. Size the oil hoses and cables sufficiently longfor oil fired systems.

Provide a gas supply line compensator in thelongitudinal direction on gas fired systems. Thisenables the gas train float to be separated at that pointwhen opening the door, and the door can be pivotedtogether with the burner.

The burner head equipment depends on thestipulations laid down by the burner manufacturer.The blast tube should protrude into the combustionchamber. Observe all instructions by the burnermanufacturer.

➔ Please contact your nearest Buderus sales office inconnection with the selection of the optimumboiler/burner combination.

4.3 Matching pressure-jet burners

Optimum combustion results require that the boilerand burner are individually matched. The LoganoS825L and S825L LN boilers and the Logano plusSB825L and SB825L LN gas fired condensing boilerstogether with appropriate burners are suitable forsystems, of which reduced emissions are required.

➔ Please contact your nearest Buderus sales office inconnection with the selection of the optimum burner.Please obtain guaranteed emission values from theburner manufacturer or from a Buderus sales office.

4 Burner

40

4


Burner

4.4 Combustion details for Logano S825L and S825L LN boilers

4.4.1 Combustion details for Logano S825L boilers, output from 1000 to 5200

40/1 Combustion chamber dimensions for the Logano S825L boilers, output from 1000 to 5200

Boiler output 1000 1350 1900 2500 3050 3700 4200 5200

Flue gas volume1)

Combustion chamberBoiler

1) To determine the pre-purge time: The flue gas volume of the combustion chamber consists of the flame tube volume(first pass) and the volume of the internal flue gas reversing chamber. The flue gas volume of the boiler comprises of the flue gas volume of the combustion chamber, the volume of the secondary heating surface and the volume of the flue gas collector.

m3

m30.681.09

0.891.40

1.211.98

1.582.58

1.903.05

2.373.67

2.864.61

3.465.44

Combustion chamber D1

D2

L1

L2

mmmmmmmm

88860022011930

98866024712180

108673026982408

1136776

31492850

123684631972878

128490135533235

138493239873650

1482101241063750

FrontHot gas reversing chamber

L3

L4

L5

mmmmmm

625190260

685190290

745190325

775190350

835190385

860190412

900257430

960257470

H1

H2

H32)

2) From a boiler output of 4200 upwards, the flame sight aperture is fitted into the boiler side.

mmmmmm

800560

–

850620

–

900685

–

925720

–

975785

–

1000815

–

1050795111

1100855122

B1 mm 1200 1300 1400 1450 1550 1600 1700 1800

Maximum door load through the burner

kNm 5 5 5 5 5 5 6 6

40/2 Combustion details for Logano S825L boilers, output from 1000 to 5200

B1L1

L2

80

~40

L3

L4

L 5

H2D1

H1

D2

1

H3

41

Burner 4


4.4.2 Combustion details for Logano S825L boilers, output from 6500 to 19200

41/1 Combustion chamber dimensions for the Logano S825L boilers, output from 6500 to 19200

Boiler output 6500 7700 9300 11200 12600 14700 16400 19200

Flue gas volume1)



m3

m34.427.13

5.508.91

6.4810.55

7.9213.04

9.7315.62

12.3220.41

14.5225.27

17.5031.76


D2

L1

L2

mmmmmmmm

1632109244854100

1780117747144300

1880126749134500

1978134453624930

2128145056615200

2326153063905900

2474160668286300

2672170672666700


L3

L4

L5

mmmmmm

1075257510

1165257560

1250257600

1340259640

1425259695

1540259735

1715294775

1830294825

H1

H2

H3

mmmmmm

1200975132

12751065145

13501150155

14251250166

15001330180

16001450190

17501630201

18501745214

B1 mm 2000 2150 2300 2450 2600 2800 3100 3300


kNm 6 6 6 6 5 4 3 3

41/2 Combustion details for Logano S825L boilers, output from 6500 to 19200

B1L1

L2

80

~40

H3

L3

L4

L5

D2 D1 H2

H1

42

4


Burner

4.4.3 Combustion details for Logano S825L LN boilers, output from 750 to 3500

42/1 Combustion chamber dimensions for the Logano S825L LN boilers, output from 750 to 3500

Boiler output 750 1000 1250 1500 2000 2500 3000 3500

Flue gas volume1)



m3

m30.681.09

0.891.40

1.211.98

1.582.58

1.903.05

2.373.67

2.864.61

3.465.44


D2

L1

L2

mmmmmmmm

88860022011930

98866024712180

108673026982408

1136776

31492850

123684631972878

128490135533235

138493239873650

1482101241063750


L3

L4

L5

mmmmmm

625190260

685190290

745190325

775190350

835190385

860190412

900257430

960257470

H1

H2

H32)


mmmm

800560

–

850620

–

900685

–

925720

–

975785

–

1000815

–

1050795111

1100855122

B1 mm 1200 1300 1400 1450 1550 1600 1700 1800


kNm 5 5 5 5 5 5 6 6

42/2 Combustion details for Logano S825L LN boilers, output from 750 to 3500

B1L1

L2

80

~40

L3

L4

L 5

D2 D1 H2

H1

H3

43

Burner 4


4.4.4 Combustion details for Logano S825L LN boilers, output from 4250 to 17500

43/1 Combustion chamber dimensions for the Logano S825L LN boilers, output from 4250 to 17500

Boiler output 4250 5250 6000 8000 10000 12000 14000 17500

Flue gas volume1)



m3

m34.427.13

5.508.91

6.4810.55

7.9213.04

9.7315.62

12.3220.41

14.5225.27

17.5031.76


D2

L1

L2

mmmmmmmm

1632109244854100

1780117747144300

1880126749134500

1978134453624930

2128145056615200

2326153063905900

2474160668286300

2672170672666700


L3

L4

L5

mmmmmm

1075257510

1165257560

1250257600

1340259640

1425259695

1540259735

1715294775

1830294825

H1

H2

H3

mmmmmm

1200975132

12751065145

13501150155

14251250166

15001330180

16001450190

17501630201

18501745214

B1 mm 2000 2150 2300 2450 2600 2800 3100 3300


kNm 6 6 6 6 5 4 3 3

43/2 Combustion details for Logano S825L LN boilers, output from 4250 to 17500

B1L1

L2

80

~40

H3

L3

L4

L5

D2 D1 H2

H1

44

4


Burner

4.5 Combustion details for Logano plus SB825L and SB825L LN gas firedcondensing boilers

4.5.1 Combustion details for Logano plus SB825L, output from 1000 to 5200

Caption1 Clean-out aperture on the hot gas side

44/1 Combustion chamber dimensions of the Logano plus SB825L gas fired condensing boilers, output from 1000 to 5200

B1L1

L2

80

~40

L3

L4

L 5

H2D1

H1

D2

1

H3

Boiler output 1000 1350 1900 2500 3050 3700 4200 5200

Flue gas volume1)



m3

m30.681.24

0.891.61

1.212.21

1.582.93

1.903.36

2.374.08

2.865.01

3.465.94


D2

L1

L2

mmmmmmmm

88860022011930

98866024712180

108673026982408

1136776

31492850

123684631972878

128490135533235

138493239873650

1482101241063750


L3

L4

L5

mmmmmm

625190260

685190290

745190325

775190350

835190385

860190412

900257430

960257470

H1

H2

H32)


mmmmmm

800560

–

850620

–

900685

–

925720

–

975785

–

1000815

–

1050795111

1100855122

B1 mm 1200 1300 1400 1450 1550 1600 1700 1800


kNm 5 5 5 5 5 5 6 6

44/2 Combustion details for Logano plus SB825L gas fired condensing boilers, output from 1000 to 5200

45

Burner 4


4.5.2 Combustion details for Logano plus SB825L, output from 6500 to 19200


45/1 Combustion chamber dimensions of the Logano plus SB825L gas fired condensing boilers, output from 6500 to 19200

B1L1

L2

80

~40

L3

L4 H2D1

H1

D2H3

L 5

1

Boiler output 6500 7700 9300 11200 12600 14700 16400 19200

Flue gas volume1)



m3

m34.427.77

5.509.60

6.4811.48

7.9214.10

9.7317.18

12.3222.23

14.5227.64

17.5034.46


D2

L1

L2

mmmmmmmm

1632109244854100

1780117747144300

1880126749134500

1978134453624930

2128145056615200

2326153063905900

2474160668286300

2672170672666700


L3

L4

L5

mmmmmm

1075257510

1165257560

1250257600

1340259640

1425259695

1540259735

1715294775

1830294825

H1

H2

H3

mmmmmm

1200975132

12751065145

13501150155

14251250166

15001330180

16001450190

17501630201

18501745214

B1 mm 2000 2150 2300 2450 2600 2800 3100 3300


kNm 6 6 6 6 5 4 3 3

45/2 Combustion details for Logano plus SB825L gas fired condensing boilers, output from 6500 to 19200

46

4


Burner

4.5.3 Combustion details for Logano plus SB825L LN, output from 750 to 3500


46/1 Combustion chamber dimensions of the Logano plus SB825L LN gas fired condensing boilers, output from 750 to 3500

B1L1

L2

80

~40

L3

L4

L 5

H2D1

H1

D2

1

H3

Boiler output 750 1000 1250 1500 2000 2500 3000 3500

Flue gas volume1)



m3

m30.681.24

0.891.61

1.212.21

1.582.93

1.903.36

2.374.08

2.865.01

3.465.94


D2

L1

L2

mmmmmmmm

88860022011930

98866024712180

108673026982408

1136776

31492850

123684631972878

128490135533235

138493239873650

1482101241063750


L3

L4

L5

mmmmmm

625190260

685190290

745190325

775190350

835190385

860190412

900257430

960257470

H1

H2

H32)


mmmmmm

800560

–

850620

–

900685

–

925720

–

975785

–

1000815

–

1050795111

1100855122

B1 mm 1200 1300 1400 1450 1550 1600 1700 1800


kNm 5 5 5 5 5 5 6 6

46/2 Combustion details for Logano plus SB825L LN gas fired condensing boilers, output from 750 to 3500

47

Burner 4


4.5.4 Combustion details for Logano plus SB825L LN, output from 4250 to 17500


47/1 Combustion chamber dimensions of the Logano plus SB825L LN gas fired condensing boilers, output from 4250 to 17500

B1L1

L2

80

~40

L3

L4 H2D1

H1

D2H3

L 5

1

Boiler output 4250 5250 6000 8000 10000 12000 14000 17500

Flue gas volume1)



m3

m34.427.77

5.509.60

6.4811.48

7.9214.10

9.7317.18

12.3222.23

14.5227.64

17.5034.46


D2

L1

L2

mmmmmmmm

1632109244854100

1780117747144300

1880126749134500

1978134453624930

2128145056615200

2326153063905900

2474160668286300

2672170672666700


L3

L4

L5

mmmmmm

1075257510

1165257560

1250257600

1340259640

1425259695

1540259735

1715294775

1830294825

H1

H2

H3

mmmmmm

1200975132

12751065145

13501150155

14251250166

15001330180

16001450190

17501630201

18501745214

B1 mm 2000 2150 2300 2450 2600 2800 3100 3300


kNm 6 6 6 6 5 4 3 3

47/2 Combustion details for Logano plus SB825L LN gas fired condensing boilers, output from 4250 to 17500

48

5


Regulations and operating conditions

5.1 Regulation extracts

The Logano S825L and S825L LN boilers and theLogano plus SB825L and SB825L LN gas firedcondensing boilers are constructed in accordance withEN 303 and with reference to the respective TRD 300.They are approved for operating pressures between 6or 10 bar and are suitable for heating systemscompliant with EN 12828.

The following must be observed when designing andoperating these systems:

● the relevant Building Regulations,

● legal requirements, and

● all locally applicable regulations.

Only qualified personnel must carry out theinstallation, the mains gas and flue gas connections,the initial start-up, the electrical wiring as well asmaintenance and repair work.

Notification and permit obligations

Subject to the Building Regulations of each country,boiler systems may require notification or approvalto/from appropriate authorities. Observe all localregulations.

Maintenance

We recommend that the system is regularly serviced,operated at least every six months and is cleaned,subject to requirements. As part of this maintenanceprocedure, check the correct function of the entiresystem.

We recommend system users enter into a maintenancecontract with a heating contractor or the burnermanufacturer. Regular maintenance is a prerequisitefor a safe and economical operation. Burnermanufacturers generally make their warranty subjectto a maintenance contract being in place.

Emission control regulations

Observe all local emission control regulations.

5.2 Operational requirements

➔ The operating conditions shown in table 48/1 arepart of the Warranty conditions for Logano S825Land S825L LN boilers and the Logano plus SB825L andSB825L LN gas fired condensing boilers.

These operating conditions are safeguarded by suitablehydraulic arrangements and boiler controls (hydraulicconnections ➔ Page 58).

Buderus will advise you regarding operatingconditions for specific applications.

The requirements for boiler water quality are also partof the warranty conditions (➔ Page 51).

5.2.1 Operating conditions of Logano S825L and S825 L LN boilers and Logano plus SB825L and SB825L LN gas fired condensing boilers

Boiler Operating conditions (guarantee conditions!)

Minimum volume flow

Minimum return

temperature

Minimum boiler output

Minimum boiler water temperature

Boiler water temp. in case of operating interruption1)

1) The lag boiler in a multi-boiler system can be switched off completely.

Maximum design

temperature spread

m3/h °C % °C °C K


–2)

2) Sizing the boiler circuit pump ➔ Page 62; minimum volume flow at burner-ON operation ➔ 49/1 and 49/2.

50 10 70 70 15–40

Logano plus SB825L and SB825L LN

Boiler –2) 50 10 70 70 15–40

Condensing heat exch.3)

3) Utilisation of condensing technology is only possible with gas burners. Maintain a return temperature of 60 °C in the case of oil fired boilers (e.g. with combi burners).

–4)

4) The maximum volume flow is 160 m3/h. If the rated volume flow of the system is higher, only a part of the volume flow can be channelled throughthe flame sight aperture fitted the condensing heat exchanger. To utilise the condensing technology to its optimum effect, the partial volume flow must be at least 20 % of the rated volume flow.

– – – – –

48/1 Operating conditions of Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

5 Regulations and operating conditions

49

Regulations and operating conditions 5


Minimum volume flow Logano S825L Minimum volume flow Logano S825L LN

5.2.2 Fuel

The Logano S825L and S825L LN boilers and theLogano plus SB825L and SB825L LN gas firedcondensing boilers can be operated with natural gas E,EL or LPG. The gas quality must meet the requirementsof the DVGW Code of Practice G 260 [Germany] orlocal requirements. To adjust the gas throughputinstall a gas meter, which gives a reading even in thelower load range of the burner.

Operation with fuel oil EL acc. to DIN 51603 is alsopossible. However, the Logano plus SB825L andSB825L LN gas fired condensing boilers may only beoperated with fuel oil for short periods and whilstmaintaining the following conditions.

Operation of the Logano plus SB825L and SB825L LN gas fired condensing boilers with fuel oil EL

● Use only a gas/oil combi burner.

● Maintain a minimum return temperature of 60 °C for the condensing heat exchanger.

● In each heating season, the system may be operated with fuel oil for a maximum of four weeks.

● Thoroughly clean the boiler or the condensing heat exchanger at least twice per annum.

During this process, separately drain and neutralisethe condensate from the flue pipe.

Boiler type Boiler output Minimum volume flowWater

m3/h

Logano S825L

1000 11

1350 15

1900 21

2500 28

3050 34

3700 41

4150 46

5200 58

6500 72

7700 85

9300 103

11200 124

12600 140

14700 163

16400 181

19200 212

49/1 Minimum volume flow of the hot water boiler Logano S825L during burner-ON operation

Boiler type Boiler output Minimum volume flowWater

m3/h

Logano S825L LN

750 11

1000 15

1250 21

1500 28

2000 34

2500 41

3000 46

3500 58

4250 72

5250 85

6000 103

8000 124

10000 140

12000 163

14000 181

17500 212

49/2 Minimum volume flow of the hot water boiler Logano S825L LN during burner-ON operation

50

5


Regulations and operating conditions

5.2.3 Corrosions protection in heating systems

Corrosion protection (primary side)

Corrosion in the heating system can be caused by poorwater quality or through air-borne oxygen within theheating system. Oxygen enters through negativepressure in the heating system. A possible cause foroxygen ingress are leaks in the heating system,negative pressure areas, an expansion vessel, which istoo small or plastic pipes without oxygen barrier.

If oxygen ingress cannot be avoided, the heatingcircuit should be separated by means of a heatexchanger.

Corrosion protection of the heating surfaces

The combustion chamber and the secondary heatingsurfaces can be damaged by heavy dust loads andhalogen compounds in the combustion air. Halogencompounds are highly corrosive. These can be found,for example, in spray cans, thinners, cleaning anddegreasing agents and in solvents. Design thecombustion air supply so that, for example, noexhaust air from chemical cleaners or paint spraybooths is induced.

How to avoid damage due to corrosion

Damage from corrosion means that the function of theheating system is impaired by corrosion. This may takethe form of blockages, boiling noise, poor circulation,rust perforations, reduced output or the formation of

cracks. Generally, this only occurs if oxygen isconstantly introduced into the heating water. Toprevent this, design the heating system, from acorrosion point of view, as a sealed system. Whenoperating a, from a corrosion point of view, sealedsystem the selection of the materials used is of lesserimportance.

Where such a sealed system cannot be created, specialcorrosion protection measures, through the treatmentof the heating water, must be implemented. Apartfrom the option of filling the heating system withdesalinated water, chemicals may also be added to theheating water. These chemicals either bind the freeoxygen present in the water or they form a corrosion-inhibiting coating on the material surfaces.

The pH value of the heating water should lie between8.2 and 9.5 (➔ 51/1). If the heating system does notcontain any aluminium components, it isrecommended to use chemicals (e.g. tri-sodium-phosphate) to alkalinise the heating water.

➔ Regular maintenance is required to ensure the long-term trouble-free utilisation of the heating system.Apart from checking the pressure, test and, if required,adjust the pH value of the heating water. If corrosioninhibitors are used, check the heating water inaccordance with the manufacturer's instructions. Alsocheck heating systems with anti-freeze in the heatingwater in accordance with manufacturer's instructions.

5.2.4 Chemical heating water additives

If, in an underfloor heating system, plastic pipes areused, which are permeable to oxygen, the corrosionprocess can be prevented by adding chemicals to theheating water. In such cases obtain a certificate fromthe manufacturer of the chemical additives, certifyingthe effectiveness and neutrality towards system

components and the materials used in the heatingsystem.

➔ Chemical additives, which are not supplied withsuch a warranty, must not be used.

51

Regulations and operating conditions 5


5.2.5 Water quality standard

Water treatment

Every boiler user must take account of the fact thatthere is no such thing as pure water where heattransfer is concerned. For that reason, particularattention must be paid to the water quality. Constantmonitoring of the water quality is an important factorfor the economical and trouble-free operation of theheating system. Water treatment also contributes toenergy savings and to the life expectancy of the entiresystem. It is an essential factor for better efficiency,functional safety, longevity and not least formaintaining the constant operational condition.

Prevention of damage due to scaling

Scaling means that solid coatings consisting of calciumcarbonate adhere to the inside of the boiler. Thesedeposits can cause local overheating and thereforelead to some risk of cracks forming in the boiler. Thereduced heat throughput caused by scaling can alsolead to a significant reduction in boiler output as well

as to increased flue gas losses. In certain circumstancesthe boiler may also emit boiling noises.

➔ Observe the requirements of the latest VdTÜVguideline (VdTÜV 1466) [Germany] or localregulations when operating the Logano S825L andS825L LN boilers and the Logano plus SB825L andSB825L LN gas fired condensing boilers.

Low pressure heating water boilers with operating temperatures up to 110 °C

Depending on the total boiler output, observe therequirements for water quality listed in table 51/1. Thewater must be treated if these requirements are notmet.

➔ Measure the quantity of fill and top-up water forsystems with a total boiler output in excess of 100 kW.Also keep a record of when and how much top-upwater was added. Also note the calcium hydrogencarbonate concentration of the top-up water.

Logano S825L and S825L LN boilers andLogano plus SB825L and SB825L LN gas fired condensing boilers

Class II boilers

Water-chemical operating mode1) low salt content low salt content saline

Electrical conductivity of the circulating water μS/cm 10–30 > 30–100 > 100–1500

Fill and top-up water

General requirements colourless, clear and free from dissolved substances

pH value at 25 °C 8–10 8–10.5 8.5–10.5

Alkaline earths (overall hardness) mmol/ldH

< 0.02< 0.1

< 0.02< 0.1

< 0.02< 0.1

Oxygen (O2) mg/l < 0.1 < 0.1 < 0.1

Circulating water

General requirements colourless, clear and free from dissolved substances

pH value 2) at 25 °C 9–10 9–10.5 9.5–10.5

Acid capacity KS 8.22) (p value) mmol/l – 0.1–0.5 0.5–5

Alkaline earths (overall hardness) mmol/ldH

< 0.02< 0.1

< 0.02< 0.1

< 0.02< 0.1

Oxygen3) (O2) mg/l < 0.1 < 0.05 < 0.02

Phosphate2)3) (PO4) mg/l 3–6 5–10 5–15

Electrical conductivity at °C μS/cm 10–30 > 30–100 > 100–1500

Diamide3) (N2H4) mg/l 0.2–1 0.2–2 0.3–3

Sodium sulphite3) (Na2SO3) mg/l – – 5–10

51/1 Operating conditions of Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers1) Systems with heavily branched pipework, i.e. in industrial and district heating systems, those with longer idle periods (even for parts of

the heating network), those operating at strongly fluctuating pressures and temperatures as well as systems with components made from diverse materials, should ideally be operated with water with a low salt content.

2) Adjust the pH or p value in operations with low salt content with tri-sodium-phosphate. Generally speaking, in operations with salt content, the alkalinity adjusts itself through the fill water consistency. Where this is not the case, adjust the pH value with tri-sodium-phosphate or possibly through the addition of sodium hydroxide. Never use ammonia. The pH value must not be higher than 9.5 if the heating water network comprises copper components.

3) In constant operations the limits are generally automatically maintained. Oxygen binders are not absolutely necessary under those circumstances. Physical and chemical processes are available should these limits be exceeded. Common chemicals are diamide and sodium sulphite. Amines that form a film are not oxygen binders. The use and type of oxygen binders must be determined for each system individually.

52

6


Heating control

6.1 Control systems

A control unit is required for the operation of theLogano S825L and S825L LN boilers and the Loganoplus SB825L and SB825L LN gas fired condensingboilers. Buderus Logamatic control systems areconstructed as modular systems. This enables theselection of a well-matching and economical unit to beprovided for all applications and stages ofdevelopment of each respective heating system.

The boiler control unit can be selected according toindividual requirements and the design of the relevantheating system:

● Control units series Logamatic 4212

● Control units series Logamatic 43xx

● Display and control units DA…

The burner mains contactors controlled by the controlunit may possibly require a burner control panel. Themains contactors may alternatively be integrated intothe Buderus control panel.

➔ The Technical Guide for the modular control systemLogamatic 4000 contains details regarding theLogamatic 4212, 4311 and 4312 control units.

6.1.1 Logamatic 4212 control unit

The Logamatic 4212 control unit is a constantcontroller for a two-stage or a modulating burneroperation. The equipment includes a controlthermostat (adjustable to 90/105 °C), a high limitsafety cut-out (adjustable to 100/110/120 °C), a boilerwater limit thermostat, a burner fault indicator, a test

button for the high limit safety cut-out, an ON/OFFswitch and two slots for hours run counters. Theauxiliary module ZM 427 available as accessorysafeguards the operating conditions of the boiler. Partof its standard delivery is an additional temperaturesensor.

6.1.2 Logamatic 4311 and 4312 control units

The Logamatic 4311 and 4312 control units comprisethe same standard safety equipment as the Logamatic4212 control unit (➔ 6.1.1). The Logamatic 4311control unit is suitable for low temperature orcondensing operation of single boiler systems with upto eight heating circuits with servomotor. For two- orthree-boiler systems, a Logamatic 4311 control unit isrequired to act as master controller for the first boiler.In addition, one Logamatic 4312 control unit isrequired for the second and third boiler as sequencecontrol units. This device combination can, togetherwith the respective function modules (accessory),control up to 22 heating circuits.

In addition, combining several control units (e.g.Logamatic 4122 with Logamatic 4323) in an ECO CANBUS connection (up to 15 addresses) offers a nearendless variety of possible functions (up to 120 heatingcircuits).

52/1 Logamatic 4311 and 4312 control units

1

2

3

Logamatic 4311 (complete equip. level (opt.))blue ➔ accessories

Logamatic 4312 (standard equipment level)blue ➔ slots for accessories

6 Heating control

53

Heating control 6


6.1.3 Lateral control unit fixture

The lateral control unit fixture, which is available asaccessory, is required for the Logano S825L and S825LLN boilers and the Logano plus SB825L and SB825L LNcondensing boilers when used in conjunction withLogamatic control units. It enables a convenientoperation of the Logamatic 4212, 4311 and 4312control units at eye level. The lateral fixture can bemounted either on the l.h. or the r.h. side of the boiler.Install the control unit on an adaptor panel on thelateral control unit fixture (➔ 53/2).

➔ You require the following accessories for installingthe Logamatic 4212, 4311 and 4312 control units:

● Burner cable

● Sensor well

Caption1 Lateral control unit fixture2 Display and control unitsDA… (➔ 54/2)3 Burner control panel


Logano plusSB825L and SB825L LN

Dimensions of thelateral control unit fixture

Boiler output Boiler outputH1)

mm

1) Lower control unit edge

1000 750 1350

1350 1000 1450

1900 1250 1500

2500 1500 1550

3050 2000 1600

3700 2500 1600

4200 3000 1600

5200 3500 1600

6500 4250 1600

7700 5250 1600

9300 6000 1600

11200 8000 1600

12600 10000 1600

14700 12000 1600

16400 14000 1600

19200 17500 1600

53/1 Dimensions for the lateral control unit fixture

53/2 Lateral control unit fixture for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

H

2

3

3

1

54

6


Heating control

6.1.4 Display and control units DA…

In their standard version, the display and control unitsDA… indicate the flow, return or flue gas temperaturewith an accuracy of ±2 K. LED indicate, whichtemperature is currently displayed. Actual values canbe transferred via 4 to 20 mA outputs. Temperaturelimits can be adjusted via the key pad. If any limit isexceeded the associated LED begins to flash and asignal is sent to one of three zero volt outputs. In itsstandard version (DA), the control unit thereforerepresents an excellent extension to the Logamaticcontrol units.

The control units DAZ, DAM and DAD also enableconstant boiler control. These may be used as analternative to the Logamatic 4212 control unit.

6.1.5 Burner control panel

A mounting plate can be fitted to the boiler at thefactory, if it is to be equipped with a burner controlpanel delivered by the burner supplier. This mounting

plate can be fitted either on the l.h. or r.h. boiler side oron the front door (➔ 53/2).

6.1.6 Buderus control panel system Logamatic 4411

The Buderus control panel system Logamatic 4411makes comprehensive control solutions available tomedium and large scale systems, which requireindividual control variations for each system. Thedepartment for control technology at your localBuderus sales office provides advice during the designphase and can develop the most suitable system

solution for each individual case. This applies equallyto PLCs and building management systems.

➔ The technical guide "Logamatic 4411 controlpanels" provides comprehensive details in thisconnection.

Component Type of instrument box

DA DAZ DAM DAD

Temperature display ✚ ✚ ✚ ✚

Burner control unit (stepped) – 2 M1)

1) Modulating

3

High limit safety cut-out – ✚ ✚ ✚

Control thermostat – ✚ ✚ ✚

Stage II – ✚ – ✚

Stage III – – – ✚

54/1 Equipment features of the display and control units DA…✚ present; – not present

54/2 Display and control units DA… for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

350 150

200 26

5

55

Heating control 6


6.2 Logamatic telecontrol system

Benefits of the telecontrol modem at a glance:● Highest security through 24 hour monitoring● Plain text fault messages; different media targets

can be combined● Simple operation at low cost via the internet "on

demand"

● Operating mode changeover via telephone (holiday home function)

● Regulating and changing control parameters from remote locations

● Displaying controller details and fault logging● Suitable for all types of systems and controls

Quick response to faults

The Buderus telecontrol modem automatically reportsoperating faults to selected targets - by e-mail, fax, textmessage, telephone etc. With a convenient PC program,the service engineer can restart the system from a remotelocation. How? All parameters can be checked andmodified via the telecommunication networks.

In addition, the telecontrol modem incorporates a webserver, which enables access to the most importantfunctions and information via a web browser. If required,local work can be efficiently planned: What measures arerequired, what spare parts are needed, are specialistsrequired?

That makes the telecontrol system from Buderus ideal formany applications: e.g. for apartment blocks, multiple-occupancy dwellings without janitor, holiday homes,installations operated by local authorities, hospitals orswimming pools. Remote monitoring is also the firstchoice for heat contracting or maintenance contracts.

➔ For further information about the Logamatictelecontrol system, see the technical guide "Logamatictelecontrol system".

55/1 Logamatic telecontrol system

E-mail

Notebook

Messages regarding operating faults or

conditions can be transmitted to

the target of choice. The service engineer

can then remedy the fault locally or via PC.

Modem connection to the control unit

Communication, monitoring and service

via telephone or modemPC or notebook with

internet browser,

e.g. Internet Explorer

Control unitTelecontrol modem Analog phone

connection

Direct connection to the control unit

Internet

PC software

ECO-SOFT

ECO-MASTERSOFT

Fax (group 3)

Telephone

(DTMF telecontrol)

Text messaging

(D1, Vodaphone,

E-Plus)

Via service engineer (locally)

Logamatic

ECO-SOFT

Logamatic Service Key

EMS (Basic controller BC10)

Logamatic 44000

control system

(ECOCAN BUS)

56

6


Heating control

6.2.1 Easycom & Easycom PRO: the telecontrol modems for the best service connections

The Easycom or Easycom PRO telecontrol modems arethe heart of the Logamatic telecontrol system. Theyconnect the control system with external devices andtransfer operating faults and conditions to one orseveral targets, subject to the time and day of the week.Examples for such targets are e-mail addresses,telephones, fax machines, mobile phones, controlPCs – depending on what is required.

Additional equipment relating to heating or buildingmanagement systems can be hooked-up via digitaland analog inputs, e.g. heat or gas meters, pressureswitches or alarm systems. In the reverse direction, thetelecontrol modem enables a complete monitoring andselection/modification of the control systemparameters.

Benefits of the Easycom at a glance:

● Cost-effective for small to medium-sized heating systems

● Compatible with all Logamatic control systems

● Monitoring and controlling a complete heating system via its parameters

● Up to three media targets, incl. e-mail addresses

● Easy to use software, even for local use

Additional benefits of the Easycom PRO at a glance:

● Also suitable for larger heating systems

● Compatible with third party controllers and components

● Up to 16 media targets

● History memory for long-term data storage

● Digital inputs for monitoring external components

● Hook-up of meters/counters for recording consumption (gas, oil, heat, hours-run)

● Modular extensions possible

● Emergency power module for stand-alone work

● Operation also possible via mobile phone networks (GSM)

The key to mobile operation

Use all options offered by the convenient and powerfuloperating software, not only from your office but alsolocally. The Logamatic Service Key TOP 2.0 is themobile high performance connection between yourcomputer and heating systems. Thanks to variousadaptors, connection to Buderus systems withLogamatic control systems is easy. Only a few mouseclicks are required to call up all operating data and toselect/modify all system parameters.

56/1 Easycom telecontrol modem

56/1 Easycom PRO telecontrol modem

56/2 Logamatic Service Key

57

Domestic hot water heating 7


7.1 Domestic hot water heating systems

The Logano S825L and S825L LN boilers and theLogano plus SB825L and SB825L LN gas firedcondensing boilers can also be utilised for centralisedheating of domestic hot water (DHW), and can becombined with any Buderus DHW cylinder. TheLogalux DHW cylinders are available as horizontal orvertical versions and in different sizes with a watercapacity of up to 6000 litres. Depending on theindividual case, they are equipped with internal orexternal indirect coils.

DHW cylinders can be used as stand-alone cylinders orcan be combined into cylinder banks. Various cylindersizes and different indirect heating sets can becombined into one cylinder primary system. Therefore,

a system solution can be found for any demand andmany different applications.

The Buderus thermal glazing Duoclean offers anumber of benefits:

● It is neutral towards DHW

● It is neutral towards pipework materials

● It is hygienic and bacteriologically sound because of its smooth, glazed and chemically resistant surface

● It is suitable for all potable water qualities

● It is resistant against thermal shock of –30 °C to 220 °C

CaptionAW Hot water outletEK Cold water inletRH Heating medium return (to the heat exchanger)RS Cylinder returnVH Heating medium flow (from the heat exchanger)VS Cylinder flow

7.2 DHW temperature control

The DHW temperature is set and controlled either bythe Logamatic 4000 control system or by a specialBuderus DHW controller. Both types are matched tothe heating control unit and suit many differentapplications.

➔ The technical guides "DHW heating" and"Logamatic 4000 modular control system" containdetailed information regarding these control units.

57/1 DHW heating according to the cylinder principle withinternal indirect coil

EKRS

VS

AW

57/2 DHW heating according to the cylinder primary principle withexternal heat exchanger

EKRH

VH

AW

7 Domestic hot water heating

58

8


System examples

8.1 Information regarding all system examples

The system examples in this chapter illustrate optionsfor the hydraulic connection of the Logano S825L andS825L LN boilers and the Logano plus SB825L andSB825L LN gas fired condensing boilers. The examplesalso indicate important control and electricalconnections for each application.

The relevant technical guides contain comprehensivedetails regarding the quantity, control connections,equipment and types of additional heating circuits aswell as regarding the installation of DHW cylindersand other consumers.

Information about additional options regarding thesystem design and design aids are available from theservice consultant of your local Buderus sales office.Specialists at your local sales office can design and

supply an appropriate control panel. Buderustherefore offers you a complete matching system incl.commissioning of your heating system.

➔ The illustrations and corresponding designinformation regarding the system examples showingthe Logano S825L and S825L LN boilers and theLogano plus SB825L and SB825L LN gas firedcondensing boilers provide a suggestion for possiblehydraulic connections. No claim to completeness isimplied.

Each system example represents a suggestion only forthat particular version of a heating system. Currenttechnical standards must be applied to all practicalimplementations.

8.1.1 Water connection

Heating circuit pumps

Circulation pumps in central heating systems must besized according to recognised technical rules.

Temperature sensor

Position a strategy flow temperature sensor (FVS) asnear as possible to the boiler system. This does notapply if the hydraulic compensation is achieved via alow loss header. Great distances between the boilersystem and the strategy flow temperature sensorimpair the control performance, particularly for boilerswith modulating burner.

➔ Design the temperature sensors for raising thereturn temperature as immersion sensors.

Dirt traps

Sediments within the heating system can lead to localoverheating, noise and corrosion. Any resulting boilerdamage is excluded from our warranty.

Prior to the installation or initial start-up, the heatingsystem must be thoroughly flushed to remove dirt andsludge from any existing system. In addition werecommend the installation of a dirt or sludge trap.

Dirt traps prevent contamination and thereforeinterruptions of the system operation at controlelements, pipework and the boiler. Install such devicesnear the lowest system point, where they must be easilyaccessible. Clean the dirt traps during every boilerservice.

➔ A low loss header (➔ Page 64) can fulfil the functionof a dirt trap.

8 System examples

59

System examples 8


8.1.2 Control unit

The operating temperature should be regulated withthe Buderus Logamatic control unit in weather-compensated mode. Individual heating circuits canalso be controlled in room temperature-dependentmode (employing room temperature sensors in areference room). For this, the servomotors and theheating circuit pumps are constantly regulated by theLogamatic control unit. The number and design of thecontrollable heating circuits depends on the Logamaticcontrol unit.

The Logamatic control unit can also regulate theburner, irrespective of whether it is a two-stage or amodulating pressure-jet burner. In case of multi-boilersystems, different types of burners can also becombined.

The electrical connections of three-phase burners andthree-phase pumps must be implemented on site.These are then controlled (230 V) by the Logamaticcontrol unit.

➔ The technical guides "Control units" includeappropriate details.

8.1.3 DHW heating

If a Logamatic control unit regulates the DHWtemperature, special functions are possible providedthe system is designed accordingly, such as the controlof a DHW circulation pump or pasteurisation toprotect against legionnaires decease.

➔ The technical guide "Sizing and selecting DHWcylinders" contains appropriate details.

8.2 Safety equipment to EN 12828

8.2.1 Requirements

The illustrations and the respective technicalinformation for system examples are not deemed to becomplete. Each system example represents asuggestion only for particular types of heating systems.Current technical standards must be applied to allpractical implementations. Design the safety

equipment in accordance with all locally applicableregulations.

EN 12828 is decisive for all safety equipment.

You may use the diagrams 60/1 of the safetyequipment for heating systems in accordance withEN 12828 as design aids.

60

8


System examples

Direct heating, operating temperature ≤ 105 °C, high limit safety cut-out ≤ 110 °C, systems > 300 kW

Caption1 Heat source ≤ 300 kW2 Shut-off valve flow/return3 Control thermostat TR4 High limit safety cut-out STB6 Temperature measuring equipment8 Diaphragm safety valve DSV 2.5/3 bar9 Lift spring safety valve LSSV ≥ 2.5 bar10 Flash trap ET, not required if, instead, a

high limit safety cut-out ≤ 110 °C and an additional maximum pressure limiter is installed for each boiler.

11 Maximum pressure valve

13 Pressure gauge15 Low water indicator LWI or alternatively a minimum pressure

limiter16 Non-return valve17 Boiler fill and drain equipment BFD19 Expansion line20 Shut-off valve - secured against unintentional closing, e.g.

leaded cap valve21 Drain upstream of the DEV22 Diaphragm expansion vessel DEV (to DIN EN 13831)

60/1 Direct heating, operating temperature ≤ 105 °C, high limit safety cut-out ≤ 110 °C, systems > 300 kW

Standard equip. of the Buderus boiler control unit

FlowThe diagram shows the safety equipment in accordance with EN 12828 for the system version shown here - completeness is not implied.

Current technical standards must be applied to all practical implementations.

Return

61

System examples 8


8.2.2 Safety equipment for the condensing heat exchanger

The condensing heat exchanger requires an additionalsafety valve with pressure gauge and air vent valve, ifa shut-off valve has been installed between the boilerand the condensing heat exchanger. If the condensing

heat exchanger is connected to the boiler withoutintermediate shut-off valve, no additional safetyequipment needs to be installed for the condensingheat exchanger.

8.2.3 Maximum operating flow temperatures

In combination with different control units, boilersmay achieve various maximum operating flowtemperatures (max. control unit setting). The burner isswitched OFF by the control unit, if these temperaturesare reached. The start-up temperature is lower by thespecified hysteresis. This generally results in maximumachievable mean operating flow temperatures asshown in table 61/3.

➔ The boiler water temperature must be at least 70 °C.It can be modulated or held at a constant level.

Control unit Max. adjust. control unit

value

Hysteresis Max.possible mean flow

temperature

°C K °C

Logamatic 4212 105/952) 5 102/922)

Logamatic 4311/43121)

1) Only applicable to the boiler control unit; heating circuits can be operated with temperatures up to 90 °C

99/952)

2) For high limit safety cut-out 110 °C

7 95/902)

DAZ/DAM/DAD 110/1002) 5 107/972)

61/3 Achievable temperatures depending on the relevant control unit

62

8


System examples

8.3 Sizing and installation

8.3.1 Boiler circuit pump in bypass as shunt pump

Volume flow – boiler circuit pump VPK

The boiler circuit pump, also referred to as shuntpump, is essential for regulating the returntemperature (flow past the sensor). Also, the controlperformance can be optimised with the assistance ofthe boiler circuit pump. This allows the number ofactivations during the heat-up process to beminimised, resulting in low emissions.

Volume flow of the heating circuits VHC

Total boiler volume flow VKttl

The head of the boiler circuit pump results from:

– the boiler pressure drop for the selected volume flow VPK

– the pipework pressure drop and

– all individual pressure drop values inside the boiler circuit A–C–D–B.

Because of the pump and system characteristics, thetotal volume flow across the boiler cannot simply becalculated by adding the individual volume flowvalues. As starting point, however, this simple addition

can provide an approximation to act as calculationbasis.

➔ Base your sizing of the pipe run in the boiler circuiton a flow rate of 1 to 1.5 m/s.

Example


– Heating system flow temperature ϑV = 90 °C

– Heating system return temperature ϑV = 70 °C

– Temperature differential (selected) ΔϑK = 50 K

Result

– VPK = 43000 l/h (distance: C–D ➔ 62/2)

– VHC = 107500 l/h (distances: C–F, D–G and E–H ➔ 62/3)

– VKttl ≈ 150500 l/h (distances: A–C and B–D ➔ 62/4)

Calculating sizesΔϑK Temperature differential for sizing the boiler circuit pump

30 to 50 K (30 K for optimum heat-up characteristics)ϑR/ϑV Return/flow temperature of the heating circuits in °CQHC Heat requirement of the heating circuits in kWQK Rated output in kWVKttl Maximum total volume flow through the boiler in l/h

(approximately)VHC Volume flow of the heating circuits in l/hVPK Volume flow of the boiler circuit pump in l/h

62/1 Example of a hydraulic layout for a single boiler system with boiler circuit pump in the bypass for the Logano S825L and S825L LN boilers or the Logano plus SB825L and SB825L LN gas fired condensing boilers

VK VPK

.

VHK

.

RK VSL

SV

SR

A

C

B

D

E H

F

G

FR

90 oC

70 oCM

PK KR

FR Return temperature sensorKR Check valvePK Boiler circuit pumpRK Boiler returnSR Servomotor – return temperature

raising facilitySV Safety valveVK Boiler flowVSL Safety flow

62/2 Formula for the volume flow of the boiler circuit pump

62/3 Formula for the volume flow of the heating circuits

VPKQK

ϑΔ K---------- 860 Kl

kWh--------------⋅=

VHCQHC

ϑV ϑR∠-------------------- 860 Kl

kWh--------------⋅=

62/4 Formula for the total volume flow of the boiler

VKttl VPK VHC+≤

63

System examples 8


8.3.2 Boiler circuit pump as primary circuit pump

Volume flow – boiler circuit pump VPK

It is recommended for systems with primary circuitpumps (e.g. for hydraulic compensation lines orneutral distributors (w/o pressure)) to integrate theboiler circuit pump into the boiler return.

For two-boiler systems, segregate the flow rate of theboiler circuit pumps according to the boiler output. Ifseveral heating circuits are constantly run with highflow temperatures and maximum volume flow, thevolume flow of each boiler circuit pump must bematched to the volume flow of the heating circuitpumps. Please observe the special requirements, e.g.maintaining a low return temperature, for systemsoperating with a gas fired condensing boiler. Wherenecessary, match the boiler circuit pump delivery tothe heating circuit flow rate.

Sizing the three-way valve

Size the three-way valve for the calculated volumeflow. In doing so, please note the pressure drop whenthe valve is fully open, as the controllability isinfluenced by the proportional pressure drop.

Primary circuit pump head

Calculate the head of the boiler circuit pump from theboiler pressure drop with the selected volume flow VPK,

the pipe pressure drop and all individual pressure dropvalues in the boiler circuit A–D–E–H.

Example

– Heat requirement of the heating circuits ΣQHC = 4000 kW

– Heating system flow temperature ϑV = 90 °C

– Heating system return temperatureϑV = 70 °C

– Total volume flow with the selected sizing factor (➔ 63/3) VKttl = VHC · 1.3

Result

– VHC = 172000 l/h (➔ 62/3)

– VKttl = 223600 l/h (distances: C–D and E–F ➔ 63/1)

Segregate the total volume flow calculated for theboiler circuit in accordance with the rated output (inthis case 50/50 %):

– VPK = 111800 l/h (distances: A–C, B–G and F–H ➔ 63/1)

Calculating sizesϑR Return temperature of the heating circuits in °CϑV Flow temperature of the heating circuits in °CQHC Heat requirement of the heating circuits in kWVKttl Total volume flow of the boiler circuit in l/hVHC Volume flow of the heating circuits in l/hVPK Volume flow of the boiler circuit pump in l/h

63/1 Example of a hydraulic layout for a two-boiler system with boiler circuit pump as primary circuit pump for the Logano S825L and S825L LN boilers or the Logano plus SB825L and SB825L LN gas fired condensing boilers

FR2

PK2

VK RK VSL VK RK VSL

SV SV

SR2 SR1

PK1

FVS

FR1

M M

VPK2

.

VHK

.

A

C

B

D

E

H

FG

VPK1

.

A

B

H

G

90 oC

70 oC

FVS Strategy flow temperature sensorFR Return temperature sensorPK Boiler circuit pumpRK Boiler returnSR Servomotor – return temperature

raising facilitySV Safety valveVK Boiler flowVSL Safety flow

63/2 Approximation formula with sizing factor for the volume flow of the boiler circuit pump of a single boiler system

63/3 Approximation formula with sizing factor for the volume flow of the boiler circuit pump of a two-boiler system

VKttl,1 VHC 1( 0, …1 2 ),⋅=

VKttl,2 VHC 1( 2, …1 5 ),⋅=

64

8


System examples

8.3.3 Low loss header

A low loss header acts as hydraulic separator betweenthe boiler and the heating circuit. Installing a low lossheader offers many benefits:

● Easy sizing of the boiler circuit pump and servomotors

● Prevention of mutual interference between the heating water volume flows in the boiler and consumer circuits

● The heat source and consumers are only supplied by the allocated water volume flows

● Applicable to single and multi-boiler systems, irrespective of the heating circuit control system

● The servomotors on both sides of the low loss header operate to optimum effect when sized correctly.

● A correctly sized low loss header can also be used as sludge trap (➔ Page 58)

● Segregation into primary and secondary circuits in case of high primary pressure drop and large distances between the boiler and the heating circuits

Sizing the low loss header

Correct sizing is vital for the low loss header function.To guarantee good separation whilst simultaneouslyensuring the sludge trap function, size the low lossheader line so that in practice, no pressure drop occursbetween the flow and the return. One can then expecta flow velocity of 0.1 to 0.2 m/s for the nominal watervolume. This also enables the simultaneous use assludge trap. Provide a sensor well of 200 to 300 mmlength in the upper region of the low loss header toensure that the heating circuit flow temperature can berecorded.

Caption1 Perforated partition2 Female connection for an air vent valve3 Female connection for a sensor well 5"4 Quick-acting valveRH Heating circuit returnRK Boiler returnVH Heating circuit flowVK Boiler flow

Example

– Total volume flow Vttl = 223.6 m3/h

– Flow velocity v = 0.2 m/s (theoretical)

Result

– Diameter of the lowLow loss header line D ≈ 0.63 m

Calculating sizesD Diameter of the low loss header line in m

VKttl Total volume flow of the boiler circuit in m3/hv Total volume flow of the boiler circuit in m/s

64/1 Basic diagram of a low loss header

1 2

3

4

VK VH

RK RH

5 x D

3 – 4 x D

D

D

64/2 Formula for sizing the low loss header

D V t t l

v------- 1

2827------------h

s---⋅=

65

System examples 8


8.4 Single boiler system with Logano S825L and S825L LN boiler: Logamatic boiler and heating circuit control unit

Information regarding all system examples (➔ Page 58 f.)

Scope

– Logano S825L and S825L LN boilers

– Logamatic boiler and heating circuit control unit

Brief system description

● Control of the minimum return temperature through overlapping the heating circuit servomotors

● Two-stage or modulating burner operation

● Simple construction

Function description

The heating circuits are controlled via the heatingcircuit modules. The boiler circuit pump delivers warmflow water to the boiler return. This raises the boilerreturn temperature. To raise the return temperature,all heating circuit servomotors are given a higherranking. The heating water volume flow to the boiler isreduced until the value set in the return temperaturecontrol has been reached by adding flow water. Oncethis set return temperature value has been reached theheating circuit control is again enabled.

Special design information

● The boiler circuit pump should, if a check valve has been fitted, run on for five minutes. If there is no check valve, the pump should run on for 60 minutes.

● When using the Logamatic control units, the maximum possible flow temperature of a heating circuit with mixer is 90 °C.

65/1 System example for one Logano S825L and S825L LN boiler with a Logamatic boiler and heating circuit control unit

VK RK

FZ

FK

R

HK1

KRPK

SH1

PH1

FV1

THV

VV

VR

FK Boiler water temperature sensorFV Flow temperature sensorFZ Auxiliary sensor for the return

temperatureHK Heating circuitKR Check valvePH Heating circuit pumpPK Boiler circuit pumpR Control unit example: Logamatic 4311RK Boiler returnSH Heating circuit servomotorTHV Thermostatic radiator valveVK Boiler flowVR Return distributorVV Flow distributor

66

8


System examples

8.5 Single boiler system with Logano S825L and S825L LN boiler: Logamatic boiler and heating circuit control unit with hydraulic separation


Scope



– Hydraulic separation

– System design in this form, if a feed pump is required; for example by sizing the heating circuit pumps or where several distribution stations are required or if the distribution stations are installed at a great distance from the boiler


● Control of the minimum return temperature through overlapping heating circuit servomotors


● Simple construction


The heating circuits are controlled via the heatingcircuit modules. To raise the return temperature, allheating circuit servomotors are given a higherranking. The heating water volume flow to the boiler isreduced until the value set temperature selected in thereturn temperature control unit has been reached byadding flow water being supplied via the hydraulicseparation. The heating circuit control is then enabledagain.


● Size the boiler circuit pump for the maximum calculated volume flow and the pressure drop inside the boiler circuit. Set the pump either to run constantly or to run on for 60 minutes.

● Allow for a low loss header or alternatively for a distributor with bypass and non-return valve.


66/1 System example for one Logano S825L and S825L LN boiler with a Logamatic boiler and heating circuit control unit and hydraulic separation

VK RK

FZ

FK

R

HK1

KR

PK

SH1

PH1

FV1

THV

VV

VR

KRWH

FK Boiler water temperature sensor(in this case installed inside the low loss header)

FV Flow temperature sensorFZ Auxiliary sensor for the return

temperatureHK Heating circuitKR Check valvePH Heating circuit pumpPK Boiler circuit pumpR Control unit example: Logamatic 4311RK Boiler returnSH Heating circuit servomotorTHV Thermostatic radiator valveVK Boiler flowVR Return distributorVV Flow distributorWH Low loss header line

(low loss header)

Alterntive to low loss header (WH)

67

System examples 8


8.6 Single boiler system with Logano S825L and S825L LN boiler: Logamatic boiler control unit


Scope


– Logamatic boiler control unit


● Control of the minimum return temperature via a separate servomotor within the boiler circuit and a boiler circuit pump as shunt pump


● Heating circuit control with Logamatic or on-site control unit


A three-way valve (SR) and the boiler circuit pump(PK), which is installed in the bypass line to the boiler,are regulated to control the return temperature. Theboiler return temperature is measured by the returntemperature sensor (FZ). If this temperature falls belowits set value, the heating water volume flow will becontinuously reduced and the bypass from the centralheating return to the central heating flow will beopened. The heating circuit volume flow remains nearconstant even during this phase of operation. Theboiler circuit pump safeguards the optimum volumeflow in the boiler circuit.



67/1 System example for one Logano S825L and S825L LN boiler with Logamatic boiler control unit

VK RK

FZ

R

HK1

KRPK

SH1

PH1

FV1

THV

VV

VRSR

FK

FV Flow temperature sensorFK Boiler water temperature sensorFZ Auxiliary sensor for the return

temperatureHK Heating circuitKR Check valvePH Heating circuit pumpPK Boiler circuit pumpR Control unit example: Logamatic 4212

with auxiliary module ZM 427RK Boiler returnSH Heating circuit servomotorSR Servomotor – return temperature

raising facilityTHV Thermostatic radiator valveVK Boiler flowVR Return distributorVV Flow distributor

68

8


System examples

8.7 Single boiler system with Logano S825L and S825L LN boiler: Logamatic boiler control unit with hydraulic separation


Scope




– System construction in this form, if a feed pump is required; for example by sizing the heating circuit pumps or where several distribution stations are required or if the distribution stations are installed at a great distance from the boiler


● Control of the minimum return temperature via a separate servomotor within the boiler circuit and a boiler circuit pump as primary circuit pump




The three-way valve (VR) is regulated to control thereturn temperature. The boiler return temperature ismeasured by the return temperature sensor (FZ).Through regulating the three-way valve (SR), theheating water volume flow to the boiler return isconstantly reduced, if the boiler return temperaturefalls below its set value. If the return temperatureexceeds its set value, the three-way valve (SR) is openedagain, and the volume flow to the heating circuit willagain increase.


● Allow for a low loss header or alternatively for a distributor with bypass and non-return valve

● Set the boiler circuit pump either to run constantly or to run on for 60 minutes

68/1 System example for one Logano S825L and S825L LN boiler with Logamatic boiler control unit and hydraulic separation

VK RK

FZ

R

HK1

PK

SH1

PH1

FV1

THV

VV

VRWH

SR

FK

FK Boiler water temperature sensor(in this case installed inside the low loss header)

FV Flow temperature sensorFZ Auxiliary sensor for the return

temperatureHK Heating circuitKR Check valvePH Heating circuit pumpPK Boiler circuit pumpR Control unit example: Logamatic 4212

with auxiliary module ZM 427RK Boiler returnSH Heating circuit servomotorSR Servomotor – return temperature

raising facilityTHV Thermostatic radiator valveVK Boiler flowVR Return distributorVV Flow distributor

69

System examples 8


8.8 Two-boiler system with two Logano S825L and S825L LN boilers: Logamatic boiler and heating circuit control unit with hydraulic separation


Scope





● Control of the minimum return temperature through overlapping heating circuit servomotors

● Serial or parallel operation as options


● Possible boiler sequence change

● Hydraulic boiler shut-off via non-return valves integrated into the boiler flow

● Automatic weather-compensated load limitation

● Boiler circuit pumps are switched off with a time delay


The heating circuits are controlled via the heatingcircuit modules. To raise the return temperature, allheating circuit servomotors are given a higherranking.

The heating water volume flow to the boiler is reduceduntil the value set in the return temperature controlunit has been reached by adding flow water suppliedvia the hydraulic separation. The heating circuitcontrol is then enabled again. The boilers arecontrolled by the sequential boiler control subject toload and time. Non-operational boilers arehydraulically shut off.




● Set the run-on times for boiler circuit pumps to between 30 and 60 minutes for the lead boiler and to five minutes for the lag boiler.

● It is recommended to split the total output to 50 % for each boiler (maximum split 60/40 %).

● This diagram can also apply to the connection of a third boiler.

69/1 System example of a two-boiler system with two Logano S825L and S825L LN boilers and Logamatic boiler and heating circuit control unit with hydraulic separation

VK RKVK RK

FRS

FK

FVS

FK

R R

HK1

KR

PK

SH1

PH1

FV1

THV

VV

VR

KRWHKR

PK

FK Boiler water temperature sensorFRS Strategy flow temperature sensorFV Flow temperature sensorFVS Strategy flow temperature sensorHK Heating circuitKR Check valve

PH Heating circuit pumpPK Boiler circuit pumpR Control unit example: Logamatic 4311

and Logamatic 4312RK Boiler returnSH Heating circuit servomotor

THV Thermostatic radiator valveVK Boiler flowVR Return distributorVV Flow distributorWH Low loss header line

Alternative to low loss header (WH)

70

8


System examples

8.9 Two-boiler system with two Logano S825L and S825L LN boilers: Logamatic boiler control unit with hydraulic separation


Scope





● Control of the minimum return temperature via a separate servomotor within the boiler circuit and a boiler circuit pump

● Serial or parallel operation as options


● Possible boiler sequence change

● The lag boiler will be hydraulically shut off with a time delay




The three-way valve (VR) is regulated to control thereturn temperature. The boiler return temperature ismeasured by the return temperature sensor (FZ).Through regulating the three-way valve (SR), theheating water volume flow to the boiler return isconstantly reduced, if the boiler return temperaturefalls below its set value. If the return temperatureexceeds its set value, the three-way valve (SR) is openedagain, and the volume flow to the heating circuit willagain increase. Non-operational boilers arehydraulically shut off.



● The run-on time of the boiler circuit pump after the burner has been switched off should be five minutes for the lag boiler and between 30 and 60 minutes for the lead boiler.


● This diagram can also apply to the connection of a third boiler.

70/1 System example of a two-boiler system with two Logano S825L and S825L LN boilers and Logamatic boiler control unit with hydraulic separation

VK RKVK RK

FZFK

FVS

FK FZ

R R

HK1

PK

SH1

PH1

FV1

THV

VV

VRWH

PK

SRSR

FK Boiler water temperature sensorFV Flow temperature sensorFVS Strategy flow temperature sensorFZ Auxiliary sensor for the return

temperatureHK Heating circuitKR Check valve

PH Heating circuit pumpPK Boiler circuit pumpR Control unit example: Logamatic 4311

and Logamatic 4312RK Boiler returnSH Heating circuit servomotor

SR Servomotor – return temperatureraising facility

THV Thermostatic radiator valveVK Boiler flowVR Return distributorVV Flow distributorWH Low loss header line

71

System examples 8


8.10 Single boiler system with Logano plus SB825L and SB825L LN gas fired condensing boilers: Logamatic boiler control unit


Scope

– Logano plus SB825L and SB825L LN gas fired condensing boilers with gas combustion


– Partial flow through the condensing heat exchanger (CHE)


● Control of the minimum return temperature via a separate servomotor within the boiler circuit and a boiler circuit pump




A three-way valve (SR) and the boiler circuit pump(PK), which is installed in the bypass line to the boiler,are regulated to control the return temperature. If thistemperature, which is measured at the returntemperature sensor, falls below its set value, theheating water volume flow will be continuouslyreduced and the bypass from the central heatingreturn to the central heating flow will be opened.

The heating circuit volume flow remains near constanteven during this phase of operation. The boiler circuitpump safeguards the optimum volume flow in theboiler circuit. The separate connection of the CHE tothe low temperature heating circuit allows a specificutilisation of condensing technology.



● The CHE circulation pump is regulated in parallel to the burner. Its head must be matched to the pressure drop in the CHE and the connecting pipes.

● The volume flow across the CHE must be greater than 20 % of the total volume flow, and must not exceed 160 m3/h.

● If shut-off valves are installed between the boiler and the CHE, an additional safety valve and pressure gauge must be provided for the CHE.

● Protect the CHE safety thermostat or with a high limit safety cut-out (to be provided on site).

71/1 System example for one Logano plus SB825L and SB825L LN gas fired condensing boiler with Logamatic boiler control unit

R

HK2

PK

SH2

PH2

FV2

THV

HK1

SH1

PH1

FV1

THV

VV

VRSR

RWT

VWT

FZVKRK

KR

KR

PWT

NTHT

FK

FK Boiler water temperature sensorFV Flow temperature sensorFZ Auxiliary sensor for the return

temperatureHK Heating circuitHT High temperature heating circuitKR Check valveNT Low temperature heating circuitPH Heating circuit pumpPK Boiler circuit pumpPWT Heat exchanger pumpR Control unit example: Logamatic 4212

with auxiliary module ZM 427RK Boiler returnRWT Return condensing heat exchangerSH Heating circuit servomotorTHV Thermostatic radiator valveVK Boiler flowVR Return distributorVV Flow distributorVWT Flow condensing heat exchanger

72

8


System examples

8.11 Single boiler system with Logano plus SB825L and SB825L LN gas fired condensing boilers: Logamatic boiler control unit with hydraulic separation


Scope

– Logano plus SB825L and SB825L LN gas fired condensing boilers with gas combustion


– System construction in this form, if a feed pump is required; for example by sizing the heating circuit pumps or where several distribution stations are required or if the distribution stations are installed at a great distance from the boiler


● Control of the minimum return temperature via a separate servomotor within the boiler circuit and a boiler circuit pump as primary circuit pump




The three-way valve (VR) is regulated to control the returntemperature. The boiler return temperature is measured bythe return temperature sensor (FZ). Through regulating thethree-way valve (SR), the heating water volume flow to theboiler return is constantly reduced, if the boiler returntemperature falls below its set value.

If the return temperature exceeds its set value, the three-wayvalve (SR) is opened again, and the volume flow to theheating circuit will again increase. The separate connectionof the condensing heat exchanger (CHE) to the lowtemperature heating circuit allows a specific utilisation ofcondensing technology.




● Set the boiler circuit pump to either run constantly or to run on for 60 minutes.



● Protect the CHE with a high limit temperature controller or with a high limit safety cut-out (to be provided on site).

72/1 System example for one Logano plus SB825L and SB825L LN gas fired condensing boiler with Logamatic boiler control unit and hydraulic separation

R

HK2

PK

SH2

PH2

FV2

THV

HK1

SH1

PH1

FV1

THV

VV

VR

KR

KR

WH

NTHT

SR

RWT

VWT

FZ

VKRKPWT

FK

FK Boiler water temperature sensor(here installed inside the low loss header)

FV Flow temperature sensorFZ Auxiliary sensor for the return temperatureHK Heating circuitHT High temperature heating circuitKR Check valveNT Low temperature heating circuitPH Heating circuit pumpPK Boiler circuit pumpPWT Heat exchanger pumpR Control unit example: Logamatic 4212

with auxiliary module ZM 427RK Boiler returnRWT Return condensing heat exchanger (CHE)SH Heating circuit servomotorSR Servomotor – return temp.

raising facilityTHV Thermostatic

radiator valveVK Boiler flowVR Return distributorVV Flow distributorVWT CHE flowWH Low loss header line

(low loss header)

Alternative to low loss header (WH)

73

System examples 8


8.12 Two-boiler system with the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers:Logamatic boiler control unit with hydraulic separation


Scope

– Logano SB825L and SB825L LN gas fired condensing boilers plus Logano S825L andS825L LN with gas combustion




● The gas fired condensing boiler is the lead boiler


● The boiler sequence can be changed, but is inadvisable

● The lag boiler will be hydraulically shut off with a time delay



The three-way valve (VR) is regulated to control thereturn temperature. The boiler return temperature ismeasured by the return temperature sensor (FZ).Through regulating the three-way valve (SR), theheating water volume flow to the boiler return isconstantly reduced, if the boiler return temperaturefalls below its set value. If the return temperatureexceeds its set value, the three-way valve (SR) is opened

again, and the volume flow to the heating circuit willagain increase.

Non-operational boilers are hydraulically shut off. Theseparate connection of the condensing heat exchanger(CHE) to the low temperature heating circuit allows aspecific utilisation of condensing technology.


● Set the run-on times for boiler circuit pumps to between 30 and 60 minutes for the lead boiler and to five minutes for the lag boiler.



● The volume flow across the CHE must be greater than 20 % of the boiler volume flow, and must not exceed 160 m3/h.


● Protect the CHE with a high limit temperature controller or with a high limit safety cut-out (to be provided on site).

● This diagram can also be applied to the connection of a third boiler.

73/1 System example of a two-boiler system with one Logano S825L and S825L LN boiler and one Logano plus SB825L and SB825L LN gas fired condensing boiler; Logamatic boiler control unit with hydraulic separation

VK RK RK VK

FK

FVS

FZFK

R2 R1

HK1

PWT

SH1

PH1

FV1

THV

HK1NTHT

SH1

PH1

FV1

THV

VV

VR

PK

SRSR

RWT

VWT

PKFZ

KR

WH

FK Boiler water temperature sensorFR Return temperature sensorFV Flow temperature sensorFZ Auxiliary sensor for the return

temperatureHK Heating circuitHT High temperature heating circuitKR Check valve

NT Low temperature heating circuitPH Heating circuit pumpPK Boiler circuit pumpPWT Heat exchanger pumpR1 Control unit example: Logamatic 4311R2 Control unit example: Logamatic 4312RK Boiler return

RWT Return - condensing heat exchanger

SH Heating circuit servomotor

THV Thermostaticradiator valve

VK Boiler flowVR Return distributorVV Flow distributorVWT Flow - condensing

heat exchangerWH Low loss

header line

74

8


System examples

8.13 Logano plus SB825L and SB825L LN gas fired condensing boilers:Dual-fuel combustion with condensing heat exchanger


Scope

– Logano plus SB825L and SB825L LN gas fired condensing boilers

– Oil and gas combi burner

– Systems with a gas cut-off contract


● Gas combustion with short-term oil combustion

● Safeguarding the operating conditions of the condensing heat exchanger (CHE) when using oil by a separate servomotor in conjunction with a return temperature controller


During gas combustion, the additional returnservomotor SRWT in the primary circuit of the CHEremains fully open. After the system changes over tooil fired operation, the return temperature control withthree-point output is activated via a controlthermostat. The mixer closes if the return temperaturefalls below its minimum value of 60 °C. The cold returnwater cannot reach the CHE. If the temperature in thiscircuit exceeds 60 °C, the mixer will again enable thesystem return.


● Install an additional safety valve and pressure gauge to CHE, if the servomotor SRWT is installed between the boiler and the CHE.

● Size the CHE circulation pump according to the pressure drop in the CHE and the pressure drop values for the DHW circuit.

● The condensate created by oil combustion must be separately drained off and neutralised (➔ Page 91 f.).

● Observe the special operating conditions for oil combustion. Your nearest Buderus sales office will advise you about suitable return temperature controllers.

● The CHE circulation pump is regulated in parallel to the burner.


74/1 Integrating the condensing heat exchanger of the Logano plus SB825L and SB825L LN gas fired condensing boilers for dual-fuel combustion

HK1

VV

VR

PWT

SH1

PH1

FV1

THV

SRWT

RWT

VWT

FR

VKRK

FR Return temperature sensorFV Flow temperature sensorHK Heating circuitPH Heating circuit pumpPWT Heat exchanger pumpRK Boiler returnRWT Return - condensing

heat exchangerSH Heating circuit servomotorSRWT Servomotor – return

temperature raising facility – condensing heat exchanger

THV Thermostatic radiator valveVK Boiler flowVR Return distributorVV Flow distributorVWT Flow - condensing

heat exchanger

75

Installation 9


9.1 Transportation and handling

9.1.1 Delivery and handling options

The Logano S825L and S825L LN boilers and theLogano plus SB825L and SB825L LN gas firedcondensing boilers are delivered as one unit.

Transport

Only use both lifting eyes for handling/lifting theboiler body with a hoist/crane. These are provided atthe front and rear top of the boiler pressure body.

The boiler body may be transported on its base frame,e.g. via rollers, over level ground.

Standard delivery

● Logano S825L and S825L LN boilers

– Boiler block with thermal insulation

– Burner door

– Flue gas collector weldment

– Flue gas mating flange

– Refractory filler (referred to as tamping clay)

– Technical documentation

● Logano plus SB825L and SB825L LN gas fired condensing boilers

– Boiler block with thermal insulation

– Burner door

– Flue gas collector weldment with integral condensing flue gas heat exchanger

– Refractory filler (referred to as tamping clay)

– Technical documentation

9.1.2 Transport dimensions

To install the boiler it is essential to size the entry intothe installation room slightly larger than the boilerdimensions. The minimum transport dimensions arelisted in table 75/1.

Please contact your nearest Buderus sales office if theseminimum dimensions cannot be met.

Logano S825LLogano plus

SB825L

Logano S825L LNLogano plus SB825L LN

Boiler room entry

Logano S825L and S825L LN boilersLogano plus SB825L and SB825L LN gas fired

condensing boilers

Boiler output Boiler outputMinimum width

mmMinimum height

mmMinimum width

mmMinimum height

mm

1000 750 1500 2000 1650 2015

1350 1000 1600 2100 1755 2115

1900 1250 1700 2200 1855 2215

2500 1500 1750 2250 1910 2265

3050 2000 1850 2350 1995 2365

3700 2500 1900 2400 2060 2415

4200 3000 2000 2500 2155 2515

5200 3500 2100 2600 2250 2615

6500 4250 2300 2800 2435 2800

7700 5250 2450 2950 2605 2950

9300 6000 2600 3100 2750 3100

11200 8000 2750 3300 2905 3250

12600 10000 2900 3400 3045 3400

14700 12000 3100 3650 3240 3600

16400 14000 3400 3950 3555 3900

19200 17500 3600 4150 3750 4100

75/1 Minimum transport dimensions of the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

9 Installation

76

9


Installation

9.2 Type of boiler room and combustion air supply

9.2.1 Combustion air supply

The construction of the boiler room and theinstallation of boilers must correspond to allapplicable local and national regulations.

Basic requirements

– Combustion air openings and lines must not be closed or blocked, if no safety equipment installed can adequately ensure that the burner can only be operated when the flow cross-section is unobstructed.

– The required cross-section must not be blocked by a closure or grille.

– Verify the adequate combustion air supply.

77

Installation 9


9.3 Installed dimensions

9.3.1 Boiler room dimensions for Logano S825L and S825 L LN boilers

77/1 Boiler room dimensions and installed dimensions for Logano S825L and S825 L LN boilers

Logano S825L Logano S825L LN Boiler room dimensions1)

1) These values are for reference only. Variations are possible subject to system.

Boiler output Boiler output

LengthL1

mm

LengthL2

mm

HeightH

mm

Lateral clearance2)

A1

mm

2) These values are for reference only, which are subject to the relevant burner. The burner door can be arranged as l.h. or r.h. opening door.

Lateral clearance2)

A2

mm

1000 750 2500

1000

3500

500

1300

1350 1000 2750 3800 1300

1900 1250 3000 4100 1300

2500 1500 3500 4100 1300

3050 2000 3500 4400 1500

3700 2500 3850 4400 1500

4200 3000 4250 4600 1550

5200 3500 4400 5100 1650

6500 4250 4800 5600 1800

7700 5250 5000

on request

1800

9300 6000 5200

on request

11200 8000 5650

12600 10000 5950

14700 12000 6700

16400 14000 7150

19200 17500 7600

77/2 Boiler room dimensions and installed dimensions for Logano S825L and S825L LN boilers (boiler foundation dimensions ➔ 87/2)

H

A 1

L1 L2

A 2

Calculate additional free space for noise attenuation measures. Select the recommended clearances between wall and boiler to enable easy access during installation, service and maintenance work. If the recommended clearances cannot be provided, check with your local Buderus sales office to ensure the functional integrity of your system.

78

9


Installation

9.3.2 Boiler room dimensions for Logano plus SB825L and SB825L LN boilers

78/1 Boiler room dimensions and installed dimensions for Logano plus SB825L and SB825L LN gas fired condensing boilers

Logano plus SB825L

Boiler output

Logano plus SB825L LN

Boiler output

Boiler room dimensions1)

1) These values are for reference only. Variations are possible subject to system.

Length2)

L1

mm

2) Length relative to the condensing heat exchanger with one tube bundle element; this dimension increases by 300 mm for condensing heat exchangers with two tube bundle elements.

LengthL2

mm

HeightH

mm

Lateral clearance3)

A1

mm

3) These values are for reference only, which are subject to the relevant burner. The burner door can be arranged as l.h. or r.h. opening door.

Lateral clearance3)

A2

mm

1000 750 2700

500

3500 700 1300

1350 1000 2950 3800 700 1300

1900 1250 3200 4100 800 1300

2500 1500 3700 4100 900 1300

3050 2000 3700 4400 900 1500

3700 2500 4050 4400 950 1500

4200 3000 4450 4600 950 1550

5200 3500 4600 5100 950 1650

6500 4250 5000 5600 950 1800

7700 5250 5200

on request

1000 1800

9300 6000 5450 1000

on request

11200 8000 5900 1000

12600 10000 6200 1000

14700 12000 6950 1000

16400 14000 7400 1050

19200 17500 7850 1050

78/2 Boiler room dimensions and installed dimensions for Logano plus SB825L and SB825L LN gas fired condensing boilers (boiler foundation dimensions ➔ 87/2)

H

A 1

L1 L2

A 2

Calculate additional free space for noise attenuation measures. Select the recommended clearances between wall and boiler to enable easy access during installation, service and maintenance work. If the recommended clearances cannot be provided, check with your local Buderus sales office to ensure the functional integrity of your system.

79

Installation 9


9.4 Optional equipment for safety equipment to EN 12828

9.4.1 Types of safety equipment

Required equipment Safety equipment version

High limit safety cut-outwith shut-down temperature ≤ 110 °C

Heat source > 300 kW

Standard equipment – safety equipment assembly

required

High limit safety cut-out set andmaximum pressure valve

required1)

1) As an alternative to the flash trap the "High limit safety cutout and maximum pressure switch" set can also be used.

Minimum pressure valve alternative to the low water indicator

79/1 Safety equipment for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

Safety component Make Component identification

Low water indicator Sasserath SYR 0933.20.0111)

1) A minimum pressure switch can be used as an alternative

TÜV HWB-96-190

Maximum pressure valve Sauter DSH 143 F 001 TÜV SDB-00-331

Minimum pressure valve Sauter DSL 143 F 001 TÜV SDBF-00-330

High limit safety cut-out Sauter RAK 74.4/3727 T STB 1006 98

79/2 Approval symbol for the safety equipment of the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

80

9


Installation

9.4.2 Boiler safety equipment assembly to EN 12828

An intermediate flow piece and a valve distributor arerequired for mounting the safety equipment.

Version Flange PN 16 acc. to DIN 2633DN 32/40/50/65/80/100/

125/150/200/250/300/350

In its standard version, the safety equipment assemblycomprises– Intermediate flow fitting– Shut-off valve– Valve distributor– Low water indicator or alternative minimum

pressure switch– Pressure gauge– Pressure gauge shut-off valve with test nipple– Maximum pressure valve

80/1 Boiler safety equipment assembly to EN 12828 (intermediate flow piece with valve distributor and valves; dim. in mm)

Intermediate flow piece

Type

Dimensions Volume Despatch weightInternal

diameter1)

1) Flange connections in accordance with DIN 2633 PN 16 (≤ 16 bar, ≤ 120 °C)

D1

DNL1

mmB1

mmB2

mm l kgVZ 50 50 300 450 225 2.3 23VZ 65 65 300 450 225 2.5 24VZ 80 80 300 450 225 3.0 25VZ 100 100 310 460 240 5.0 30VZ 125 125 320 475 250 7.0 35VZ 150 150 330 490 265 11.0 40VZ 200 200 345 515 290 18.0 53VZ 250 250 365 540 320 29.0 66VZ 300 300 385 565 345 41.0 82VZ 350 350 395 580 360 48.0 111VZ 400 400 415 610 385 65.0 125

80/2 Specification of the intermediate flow piece for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

BAR

1

1 2 3 4 5 6 7

L1

D1

B1 B2 ~510

700

1 Flow2 Level limiter

(as low water indicator, option)3 Pressure gauge (with test function)

4 Maximum pressure valve5 Level limiter (as minimum pressure switch)6 Shut-off valve DN 207 Temperature sensor (variable output control, option)

81

Installation 9


9.4.3 Intermediate return piece

An intermediate return piece can be installed to enablethe fitting of the safety expansion line and for heightcompensation for the intermediate flow piece (➔ 80/2).This piece provides a connection for a further sensor.

➔ A fully functioning intermediate return piece isalready integrated into the return temperature raisingfacility set (➔ Page 84).

Caption1 Spare coupling R5"; length 120 mm2 Safety expansion line connection

81/1 Dimensions of the intermediate return piece for the Logano S825L and S825L LN and the Logano plus SB825L and SB825L LN gas fired condensing boilers (dim. in mm)

D3

550

350

120

D1

1

2

D2

Intermediate return piece

Type

Dimensions Volume Weight

Internal diameter Diameter Internal diameter

D11)

DN

1) Types of flange connections: flange PN 16 acc. to DIN 2633

D2

mmD3

DN l kg

RZ 32 32 60.3 15 1.2 8

RZ 40 40 60.3 20 1.2 9

RZ 50 50 60.3 25 1.2 10

RZ 65 65 76.1 32 2.1 13

RZ 80 80 88.9 40 3.2 15

RZ 100 100 114.3 50 5.4 21

RZ 125 125 139.7 65 7.3 28

RZ 150 150 168.3 65 10.4 34

RZ 200 200 219.1 80 19.3 40

RZ 250 250 273.0 125 29.1 61

RZ 300 300 323.9 125 43.9 65

RZ 350 350 355.6 150 53.0 85

RZ 400 400 406.4 150 64.0 105

81/2 Specification of the intermediate return piece for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

82

9


Installation

9.4.4 Safety valve

The ARI safety valve, Fig. 903, can be fittedimmediately to the boiler connector VSL (e.g. ➔ 12/1).During manufacture the internal diameter of theboiler connector will be matched to the requiredinternal diameter of the safety valve. A mating flangeis offered as accessory for the outlet side of the safetyvalve.

Captiona Leg lengthA Outletb Leg heightE InletH Heightx Top clearance

82/1 Safety valve for water heating systems in accordance with the requirements of EN 12828

x

H

b

aE

A

Safety valve made by ARI, Fig. 903 Internal diameter – valve size1)

1) Flange PN 16 acc. to DIN 2633

DN 32 DN 40 DN 50 DN 65 DN 80 DN 100 DN 125 DN 150

Internal diameter – outlet1) A DN 50 65 80 100 125 150 200 250

Max. response pressure bar 10 10 10 10 10 10 10 10

Leg length a mm 110 115 120 140 160 180 200 225

Leg height b mm 115 140 150 170 195 220 250 285

Height H mm 330 390 435 545 610 690 845 890

Top clearance x mm 200 250 300 350 400 500 500 500

82/2 Specification and dimensions of the safety valve supplied by ARI, Fig. 903

Safety valve made by ARI, Fig. 903 Internal diameter – valve size1)

1) Flange PN 16 acc. to DIN 2633

Max. response pressure DN 32 DN 40 DN 50 DN 65 DN 80 DN 100 DN 125 DN 150

applicable to boilers with max. rating of

bar kW kW kW kW kW kW kW kW

2.5 565 870 1360 2300 3480 5440 7120 9900

3.0 649 1000 1560 2640 4000 6250 8190 11400

4.0 810 1250 1950 3300 5000 7800 10200 14200

5.0 960 1480 2310 3900 5910 9240 12100 16900

6.0 1100 1700 2660 4500 6820 10600 14000 19400

8.0 1390 2140 3350 5660 8580 13400 17600 24500

10.0 1670 2570 4010 6790 10300 16000 21100 29300

82/3 Performance of the safety valve made by ARI, Fig. 903 (Fig. ➔ 82/1)

83

Installation 9


9.4.5 Flash trap

Provide flash traps in accordance with EN 12828 forboilers with a rated output > 300 kW. Heating systemsdo not require the installation of a flash trap. Thisnecessitates the installation of an additional high limitsafety cut-out and an additional maximum pressureswitch. Install the flash traps in the safety valve blow-off line. These separate the steam and the waterphases. Install a water drain at the lowest point of theflash trap. This enables any heating water, which maybe expelled, to be safely observed and drained off. Leadthe steam blow-off line from the highest point of theflash trap outdoors.

CaptionD DiameterH Height

83/1 Flash trap dimensions and descriptions

D2

D1H

D3

D4

D5

Safety valve

Flash trap Line between the safety valve and the

flash trap

Blow-off line

Type Diameter Blow-off pressure

Height Weight Length Number of bends

Length Number of bends

D1

DND2

DND3

DND4

DND5

mm

H

DN/DN bar mm kg m m

25/40

et 40 25 40 50 50 165 ≤ 5 346 2.0

≤ 5 ≤ 2 ≤ 10 ≤ 3

et 50 32 50 65 65 165> 5≤ 10

346 2.2

32/50

et 50 32 50 65 65 165 ≤ 5 346 2.2

et 65 40 65 80 80 283> 5≤ 10

440 6.8

40/65

et 65 40 65 80 80 283 ≤ 5 440 6.8

et 80 50 80 100 100 283> 5≤ 10

440 7.2

50/80

et 80 50 80 100 100 283 ≤ 5 440 7.2

et 100 65 100 125 125 391> 5≤ 10

616 14.2

65/100

et 100 65 100 125 125 391 ≤ 5 616 14.2

et 125 80 125 150 150 450> 5≤ 10

776 19.5

80/125

et 125 80 125 150 150 450 ≤ 5 776 19.5

et 150 100 150 200 200 500> 5≤ 10

896 28.0

100/150 et 150 100 150 200 200 500 ≤ 5 896 28.0

83/2 Selection table for a flash trap to be installed downstream of the safety valves with internal diameters D/G/H

84

9


Installation

9.4.6 Return temperature raising set

The return temperature raising set, which is offered asan accessory, can be included in the boiler design toensure that the required minimum return temperatureis maintained. This set may be installed in heatingsystems equipped either with a low loss header or witha low pressure distributor (system examples ➔ 68/1,70/1, 71/1 and 72/1).

This set will be supplied pre-assembled and thereforesubstantially reduces the time required for thecompletion of the boiler system. This set enables thesimple completion of the system installation.

➔ The function of the intermediate return piece(➔ 81/1) is already integrated and can therefore not begiven an alternative use.

➔ Alternative types of the return temperature raisingset (e.g. with bypass pump, horizontal layout etc.) onrequest.

➔ As part of the system design phase, ensure that thesystem is matched to the specific prevailing conditions.

➔ Dimensions and specifications of the returntemperature raising set on request

Caption1 Shut-off damper with notched lever2 Three-way mixing valve with actuating drive3 Circulation pump4 Non-return valve or check valve5 Connection for pressure maintaining equipmentRK ReturnVK Flow

84/1 Standard delivery of the return temperature raising set (highlighted) for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

BAR

2

1

3

4

5

1

VK

RK

85

Installation 9


9.5 Noise attenuation accessories

9.5.1 Requirements

The necessity and extent of noise attenuationmeasures depend on the sound level and the nuisancecreated by this noise emission. Buderus offers threenoise attenuating sets specially matched to the LoganoS825L and S825L LN boilers and the Logano plusSB825L and SB825L LN gas fired condensing boilers.These may be supplemented by additional (on-site)noise attenuating measures.

These measures which may be taken on site, includeanti-vibration pipe cleats, compensators in connectinglines and flexible joints/unions attached to thebuilding structure. The noise attenuating equipmentrequires additional space, which must be taken intoconsideration during the design phase.

The application of noise attenuating measuresdepends on the building use and the requirementsmade of the adjoining rooms and the vicinity outside.

9.5.2 Flue gas silencer

A significant proportion of combustion noise can betransferred to the building by the flue gas system.Silencers designed for this purpose can noticeablyreduce the associated noise level.

The flue gas silencer shown in Fig. 85/1 providesattenuation, subject to version, of between 10 to15 dB(A) or 20 to 25 dB(A) in the flue pipe. The flue gassilencers are available in sheet steel and stainless steel.

For gas fired condensing boiler systems, only flue gassilencers made from corrosion resistant stainless steelwith condensate drain may be used.

CaptionD1 Flue gas inlet and outlet diametersD2 Silencer diameterL Silencer length

➔ Maximum flue gas pressure drop inside the flue gas silencer: 50 Pa

85/1 Flue gas silencers for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

L1

D2

D1

Flue gas silencer Dimensions Weight

Diameter Length

D1 D2 L1 L1

Internal diameter – connection

DN mm mm

Noise attenuation approx. 15 dB(A)1)

mm

1) 15 dB(A) and 25 dB(A) can be expected


mm


kg


kg

250 254 550 1000 1500 78 115

315 320 700 1020 1520 112 164

400 402 900 1050 1550 169 245

500 505 900 1340 1840 199 270

630 636 1100 1340 1840 313 440

800 799 1300 1370 2370 400 667

1000 1005 1500 1380 2380 450 763

1250 1265 1700 1390 2390 527 870

85/2 Dimensions of the flue gas silencers for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

86

9


Installation

9.5.3 Burner silencer hood

The airborne noise, which the burner creates duringoperation, may be reduced by a burner silencer hood.

Take the additional space required for removing thesilencer hood into consideration when planning theboiler room.

Buderus offers burner silencer hoods, which aretailored to each individual pressure-jet burner. Fordetails of the space requirement, dimensions andattenuation values, contact your local Buderus salesoffice.

9.5.4 Anti-vibration boiler mounts

Anti-vibration boiler mounts prevent the transmissionof vibration to the building foundations. For theLogano S825L and S825L LN boilers and the Loganoplus SB825L and SB825L LN gas fired condensingboilers, these are made from polyurethane (PUR) witha thickness of 12 mm. Position the anti-vibration stripsflush with the outside edge of the base frame. Toachieve the required attenuation, ensure that the baseon which the boiler is to be placed is perfectly level(foundation dimensions ➔ Page 87).

When designing anti-vibration boiler mounts youshould consider that the boiler build height andtherefore the location of pipework connections willalter as a result of these measures. To compensate forthe springing of the boiler mounts and to minimise thetransmission of vibrations via the water connections,the installation of pipe compensators into the heatingwater pipes is also recommended.

The size of the anti-vibration boiler mounts must beappropriate for each respective boiler.

Calculate the maximum permissible operating weightof the boiler from the recommended working range of0 to 0.3 N/mm2 (representing 0 to 3 kg/cm2) and thebase of the anti-vibration strips (➔ 86/2). Ensure theeven weight distribution of the boiler support acrossthe whole surface area of the anti-vibration strips.

86/1 Anti-vibration mounts for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

L1

B 1

B 2B 2

Logano S825LLogano plus SB825L


Dimensions Maximum possible operating weight

L1

mmB1

mmB2

mm tBoiler output Boiler output

1000 750 2100 910 55 6.9

1350 1000 2350 910 55 7.8

1900 1250 2560 930 65 10.0

2500 1500 3060 1130 65 11.9

3050 2000 3060 1130 65 11.9

3700 2500 3410 1150 75 15.3

4200 3000 3920 1260 80 18.8

5200 3500 3920 1510 80 18.8

6500 4250 4280 1510 80 20.5

7700 5250 4480 1520 85 22.8

9300 6000 4650 1610 80 44.6

11200 8000 5050 1630 80 48.5

12600 10000 5320 1890 80 51.1

14700 12000 6000 1890 95 57.6

16400 14000 6390 2100 100 76.7

19200 17500 6790 2100 100 81.5

86/2 Dimensions of the anti-vibration mounts for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

87

Installation 9


9.5.5 Boiler foundation

To ensure an even weight distribution, the LoganoS825L and S825L LN and the Logano plus SB825L andSB825L LN gas fired condensing boilers are equippedwith a stable base support formed from channelsections. Any foundation provided should not reachthe side panels to prevent the transmission ofvibration.

If appropriate boiler mounts have been provided asanti-vibration measure (➔ Page 86), check that thefoundation is level to within ± 1 mm. This ensures thatthe boiler mounts are evenly loaded.

87/1 Boiler foundation for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

≥ 50

≥ 50

B3

B1

B2

L2

L1


SB825L


Plinth Base frame Channel section

Length Width Length Width Height Width

L1

mmB1

mmL2

mmB2

mmH

mmB3

mmBoiler output Boiler output

1000 750 2200 1010 2100 910 120 55

1350 1000 2450 1010 2350 910 120 55

1900 1250 2660 1030 2560 930 160 65

2500 1500 3130 1230 3030 1130 160 65

3050 2000 3160 1250 3060 1150 200 75

3700 2500 3510 1250 3410 1150 200 75

4200 3000 3920 1350 3820 1250 200 75

5200 3500 4020 1610 3920 1510 220 80

6500 4250 4380 1610 4280 1510 220 80

7700 5250 4580 1620 4480 1520 240 85

9300 6000 4750 1710 4650 1610 240 85

11200 8000 5150 1730 5050 1630 280 95

12600 10000 5420 1990 5320 1890 280 95

14700 12000 6100 1990 6000 1890 280 95

16400 14000 6490 2200 6390 2100 320 100

19200 17500 6890 2200 6790 2100 320 100

87/2 Dimensions of the boiler foundation for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

88

9


Installation

9.6 Additional accessories

9.6.1 Drain connection and blow-down valve assembly

A drain connection in line with Fig. 88/2 isrecommended to enable the boiler to be drainedquickly and, if required, to blow down boiler sludge.

Caption1 Logano S825L / S825L LN or

Logano plus SB825L / SB825L LN2 Boiler drain3 Drain valve

88/2 Drain connection version for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

1

2 3

89

Installation 9


9.6.2 Walk-on boiler cover

As accessory, Buderus offers a walk-on boiler cover.Included in this accessory is a ladder and a safety railwith foot board. The walk-on cover is fitted before theboiler is delivered to site. The safety rails and laddermust be fitted on site. The ladder may be fitted either to

the l.h. or the r.h. side of the boiler. Please state yourpreferred side when ordering the walk-on boiler cover.In case of gas fired boilers, the ladder should be fittedon the opposite side to the gas supply line.

89/1 Dimensions of the walk-on boiler cover for the Logano S825L and S825L LN and the Logano plus SB825L and SB825L LN gas fired condensing boilers; safety rail and ladder are options; (dim. in mm)


SB825L

Logano S825L LNLogano plusSB825L LN

Walk-on boiler cover

Dimensions Weight1)

1) Including safety rail and ladder

Length Width Height

kgL

mmB

mmH

mmBoiler output Boiler output

1000 750 2150 900 1505 155

1350 1000 2400 900 1605 165

1900 1250 2600 1000 1705 195

2500 1500 3100 1100 1755 235

3050 2000 3100 1100 1855 235

3700 2500 3450 1100 1905 255

4200 3000 3800 1200 2005 305

5200 3500 3950 1200 2105 315

6500 4250 4300 1400 2305 405

7700 5250 4500 1400 2455 420

9300 6000 4800 1600 2605 490

11200 8000 5100 1800 2755 590

12600 10000 5400 1800 2905 610

14700 12000 6100 1800 3105 680

16400 14000 6600 2000 3405 900

19200 17500 7000 2000 3605 980

89/2 Specification of the walk-on cover for the Logano S825L and S825L LN boilers and the Logano plus SB825L and SB825L LN gas fired condensing boilers

L B

H10

05

1

2

Caption1 Safety rail (option)2 Ladder (option) for

fitting to l.h. or r.h. side

90

10


Flue gas system

10.1 Requirements

10.1.1 General information

Consult EN 13384 as basis for calculating and sizingthe flue gas system. The following formula can be usedto calculate the flue gas flow:

For oil combustion systems (CO2 content 13.5 %):

For gas combustion systems (CO2 contents 10.5 %):

You will find easy to use tables showing the requiredcurves for the Logano S825L and S825L LN and the

Logano plus SB825L and SB825L LN series in thetechnical guide "Chimney Stack Technology".

The combustion output results from the selected ratedoutput and the relevant efficiency (➔ Page 34).

The requirements for the flue gas system and flue piperouting can be derived from the results of the above.

Calculating sizesηK Boiler efficiency in %mFlue gas, oil Flue gas flow rate for oil combustion in kg/smFlue gas, gas Flue gas flow rate for gas combustion in kg/sQF Combustion output in kWQN Rated output in kW

10.1.2 Special information regarding flue gas systems for gas fired condensing boilers

Correct sizing of the flue gas system is a prerequisite forfunction and operation of a gas fired condensingboiler. Only flue pipes, which meet BuildingRegulations, may be used. Also observe therequirements laid down on the permit when selectinga flue gas system.

The flue gas system must be designed as duct systemwith secondary ventilation over its entire length, ifoverpressure must be expected inside the flue gassystem, and the flue gas system runs through occupiedrooms. Observe all local and national requirements.

10.1.3 Material requirements for flue gas systems used with gas fired condensing boilers

The flue pipe material must be resistant to the flue gastemperatures which will occur, to moisture and acidiccondensate. Suitable materials are flue pipes madefrom stainless steel as well as other moisture-resistantchimney stacks.

Flue pipes are categorised acc. to their maximum fluegas temperature (80 °C, 120 °C, 160 °C and 200 °C).For gas fired condensing boilers, the flue gas

temperature can be below 40 °C, independent of themaximum flue gas temperature. Therefore, moisture-resistant chimney stacks must also be suitable fortemperatures below 40 °C. A suitable flue pipe must beapproved by the Deutsche Institut für Bautechnik,Berlin [Germany] or your locally applicable authority.

For moisture-sensitive stacks, the updraught at thestack inlet must not be higher than 0 Pa.

90/1 Formula for flue gas flow in oil fired systems

90/2 Formula for flue gas volume flow for gas combustion

mfluegas,oil QF4 104,10000--------------- kg

kWs-----------⋅=

mfluegas,gas QF4 082,10000--------------- kg

kWs-----------⋅=

90/3 Combustion output formula

QFQN

ηK------- 100 %⋅=

10 Flue gas system

91

Draining condensate 11


11.1 Condensate

11.1.1 Production

When burning fuels containing hydrogen, watervapour condenses inside the condensing heatexchanger and in the flue gas system. The quantity ofcondensate created per kW/h depends on the

carbon:hydrogen ration of the fuel. The quantity ofcondensate also depends on the return temperature,the amount of excess air during combustion and theheat generator loading.

11.1.2 Draining the condensate

Condensate from gas fired condensing boilers must becorrectly introduced into the public sewer system. Thecondensate must be neutralised before introductioninto the sewer, since the rated output of the Loganoplus SB825L and SB825L LN gas fired condensingboiler is higher than 200 kW. Check specifically, thatthe neutralising system is suitable for oil combustionsystems, when using the boiler in dual-fuel mode.

The following formula applies to the precisecalculation of the annual quantity of condensate:

Calculating sizesVK Condensate volume flow in l/p.a.QF Rated output of the heat source in kWmK Spec. quantity of condensate in kWh/kg

(assumed specific weight ρ = 1 kg/l)bVH Hours of full utilisation (acc. to VDI 2067) in h/p.a.

➔ It is recommended that you check the localregulations regarding the introduction of condensateinto the public sewer in good time before theinstallation.

11.2 Neutralising system NE 2.0

11.2.1 Positioning

The neutralising system NE 2.0 can be used for gascombustion, (applications and limitations ➔ Page 92).Install it between the condensate outlet of the gas firedcondensing boiler and the connection to the publicsewer. Position the neutralising system behind oralongside the gas fired condensing boiler. To enablethe condensate to run freely, position the neutralisingsystem at the same height as the gas fired condensingboiler. As an alternative, it may also be installed belowthis height.

➔ Implement the condensate line in accordance withthe country-specific requirements using suitablematerials, for example polypropylene.

91/1 Formula for the annual condensate volume flow

VK QF mK bVH⋅ ⋅=

Dimensions andconnections

Neutralising system NE 2.01)

1) Weight in the operating state: approx. 60 kg

WidthDepthHeight

mmmmmm

545840275

InletOutletDrain

DNDNDN

40/202)

2020

2) Hose connection – option

91/2 Dimensions and connections of the neutralising system NE 2.0

11 Draining condensate

92

11


Draining condensate

11.2.2 Equipment

The neutralising system NE 2.0 comprises arectangular plastic housing with separate chambersfor the neutralising medium and the neutralisedcondensate, a level-controlled condensate pump andan integral electronic control unit.

The level-controlled condensate pump has a head ofapprox. 2 m. Where necessary, the head may beincreased to approx. 4.5 m by means of a pressureraising module.

The integral electronic control unit containsmonitoring and service functions:

– Burner safety shutdown in conjunction with Buderus Logamatic control units

– Overrun protection

– Display for indicating the need to change the neutralising granulate

– Operating condition display

– Transmission of fault signals (e.g. to the Logamatic telecontrol system)

11.2.3 Neutralising medium

Fill the neutralising system NE 2.0 with 17.5 kgneutralising granulate. The pH value of thecondensate is raised from 6.5 to 10 by contact with theneutralising medium. Condensate with that pH valuecan be safely drained into the domestic sewer system.

The length of effectiveness of the granulate depends onthe volume of neutralised condensate. Replaceconsumed neutralising granulate, when the pH valueof the neutralised condensate falls below 6.5. Refillgranulate when the signal lamp illuminates.

11.2.4 Pump rate diagram

The head of the neutralising system NE 2.0, which issubject to the pump rate, is shown in Fig. 92/1. Whenusing the pressure raising module for the neutralisingsystem NE 2.0, the heads are added together, as twopumps with identical characteristics are switched inseries. Consider the pressure drop in the pipeworkwhen calculating the actual pump head.

A maximum condensate volume of approx. 200 l/hcan be applied on account of the limited duration forwhich the condensate pump of the neutralising systemNE 2.0 is switched ON.

➔ Two sets of neutralising system NE 2.0 can be run inparallel, if greater condensate volumes must beprocessed. Buderus also offer alternative neutralisingsystems for heating systems with a higher output andtherefore greater condensate volumes. In such cases,please contact your nearest Buderus sales office.

Example

A Logano plus SB825L gas fired condensing boiler withan output of 3050 kW (hot water inlet temperature intothe condensing heat exchanger 30 °C), will createapprox. 200 litres of condensate per hour heatingoperation. For this volume, a neutralising set NE 2.0would be sufficient.

Captionh HeadV Delivery flow rate

92/1 Pump rate diagram for the neutralising system NE 2.0

0 10 20 30 40 50

h/m

3.0

2.5

2.0

1.5

1.0

0.5

0

lmin

V/

93

Selection aids 12


12.1 Boiler selection

Select the suitable boiler type and size subject to therequirements of the intended project. Project-dependent requirements could be:

– Favourable cost/benefit ratio

– High levels of efficiency

– Stringent emission requirements

Use the boiler selection questionnaire to choose aLogano S825L and S825L LN or Logano plus SB825Land SB825L LN. This enables you to record the specificrequirements of the intended project in a clearmanner.

➔ Fig. 93/1 illustrates a sample questionnaire whichhas already been completed (photocopy template➔ 94/1).

12.2 Boiler selection questionnaire

93/1 Boiler selection questionnaire for a Logano S825L and S825L LN or Logano plus SB825L and SB825L LN; photocopy template ➔ 94/1

Project:

Date: Contact:

Project details:Required values Required boiler size

Rated output kW

Fuel Fuel oil EL kWh/kg

Natural gas kWh/m 3

Dual-fuel combustion (fuel oil EL and natural gas) yes no

Operating temperatures ˚C/˚C

Operating pressure bar

Miscellaneous

Emissions and environmental protection:

Compulsory requirements:

1. BImSchV TA Luft

Flue gas loss % 5 T A Luft

LRV Regional Directive

Required values

NO X mg/m 3

CO mg/m 3

SO X mg/m 3

Dust mg/m 3

O 2 content (reference value) % vol.

Miscellaneous

Economy:Required values Required values

˚C

Flue gas loss %

%

%

Miscellaneous

Condensing heat exchanger (only for gas combustion) at a water inlet temperature of ˚C

Output kW

˚C

Miscellaneous

Burner details:Make A Make B With make A With make B

Required values Required boiler size

Combustion chamber length mm

Combustion chamber diameter mm

Combustion chamber volume load MW/m 3

Miscellaneous

The highest boiler output determines the boiler type and size for the given requirements

Sample house Miller

21 January 2005 R. Meier

1800

9.0

100/70

9

Logano S825L-1900

Logano S825L-1900

Logano S825L-1900/10

X

9

X

80

3

190

7.5 (13.5 % CO 2)

Logano S825L-2500 – 191 ˚C

Logano S825L-2500 – 191 ˚C

~ plus > 150

35

Logano plus SB825L-1900 – 160 kW

2480

804

1.5 1.5

666

2230

BA

X

Logano S825L-2500 2500

Logano S825L-1900 1900

Logano S825L-3050 1900

➊

➊

➊

➋

➋

➋

➋

➌➍

Determine a suitable boiler output➋ subject to the required values ➊using the specifications for theLogano S825L and S825L LN boilers(➔ 3.2) or the Logano plus SB825Land SB825L LN gas firedcondensing boilers (➔ 3.3). Selectthe boiler type to be used to meetall requirements on the basis of thelargest determined boiler size. TheMüller sample house 93/1 indicatesthat, in line with the requirementslaid down ➊, either a LoganoS825L-3050 boiler with a burnermade by A ➌ or a Logano S825L-2500 boiler with a burner made byB ➍ would be suitable. In line withthe specified requirements, aLogano S825L-2500 boiler with aburner made by B should beselected.

12 Selection aids

94

12


Selection aids

94/1 Boiler selection questionnaire for a Logano S825L and S825L LN or a Logano plus SB825L and SB825L LN

Project:

Date: Contact:

Project details:Required values Required boiler size

Rated output kW

Fuel Fuel oil EL kWh/kg

Natural gas kWh/m 3

Dual-fuel combustion (fuel oil EL and natural gas) yes no

Operating temperatures ˚C/˚C

Operating pressure bar

Miscellaneous

Emissions and environmental protection:

Compulsory requirements:

1. BImSchV TA Luft

Flue gas loss % 5 T A Luft

LRV Regional Directive

Required values

NO X mg/m 3

CO mg/m 3

SO X mg/m 3

Dust mg/m 3

O 2 content (reference value) % vol.

Miscellaneous

Economy:Required values Required boiler size

˚C

Flue gas loss %

%

%

Miscellaneous

Condensing heat exchanger (only for gas combustion) at a water inlet temperature of ˚C

Output kW

˚C

Miscellaneous

Burner details:Make A Make B With make A With make B

Required values Required boiler size

Combustion chamber length mm

Combustion chamber diameter mm

Combustion chamber volume load MW/m 3

Miscellaneous

The highest boiler output determines the boiler type and size for the given requirements.

95

Appendix 13


AApplications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

BBoiler efficiency . . . . . . . . . . . . . . . . . . . . . . . .6, 34, 35

Boiler foundation . . . . . . . . . . . . . . . . . . . . . . . . .5, 87

Boiler house dimensionsLogano & SB825L LN . . . . . . . . . . . . . . . . . . . . . . . . .78Logano S825L LN boiler . . . . . . . . . . . . . . . . . . . . . . .77

Boiler safety equipment assembly . . . . . . . . . . . . . .80

BurnerMatching pressure-jet burners . . . . . . . . . . . . . . . . . . .39Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Silencer hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86

Burner selection . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

CCalorific value (net) . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Chemical additives . . . . . . . . . . . . . . . . . . . . . . . . . .50

Combustion air supply . . . . . . . . . . . . . . . . . . . . . . .76

Combustion chamber volume load . . . . . . . . . .32, 33

Combustion specification . . . . . . . . . . . . . . . . . 40 - 47

Condensate pump . . . . . . . . . . . . . . . . . . . . . . . . . . .92

Condensate quantity . . . . . . . . . . . . . . . . . . . . . . . . .91

Condensing technologyDesign tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8Matching the technology to the heating water . . . . . . .7Rated output (CHE) . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Connections . . . . . . . . . . . . . . . . . . . . . . . . .26, 27, 28

Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96

Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52

Control systemsBurner control panel . . . . . . . . . . . . . . . . . . . . . . . . . .54Control panel system Logamatic 4411 . . . . . . . . . . . .54Control units Logamatic 4311 and 4312 . . . . . . . . . . .52Display and control units DA… . . . . . . . . . . . . . . . . . .54Logamatic 4212 control device . . . . . . . . . . . . . . . . . .52Logamatic telecontrol system . . . . . . . . . . . . . . . . . . .55

Control unit fixture on the side . . . . . . . . . . . . . . . . 53

Corrosion protection . . . . . . . . . . . . . . . . . . . . . . . . .50

DDelivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75

DHW temperature control . . . . . . . . . . . . . . . . . . . .57

DirectivesWater quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

Display and control units DA… . . . . . . . . . . . . . . . . .54

Domestic hot water heating . . . . . . . . . . . . . . . .57, 59

Drain connection . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

EEfficiency considerations . . . . . . . . . . . . . . . . . . . . . . . 8

Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

FFlash trap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

Flow pressure dropHot gas pressure drop . . . . . . . . . . . . . . . . . . . . . 30, 31Pressure drop (primary circuit) . . . . . . . . . . . . . . . . . . 29

Flow safety line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Flue gas loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Flue gas systemGeneral notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90Material requirements for flue gas systems used with gas fired condensing boilers . . . . . . . . . . . . . . . . . . . . . . . 90Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90Special notes for gas fired condensing boilers . . . . . . . 90

Flue gas temperature . . . . . . . . . . . . . . . . . . . . . . . . 37

HHandling options . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Hydraulic separation . . . . . . . . . . . . 66, 68, 69, 72, 73

IIntermediate return piece . . . . . . . . . . . . . . . . . 81, 84

Investment costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

LLadder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Latent heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Logano & SB825L LNBoiler house dimensions . . . . . . . . . . . . . . . . . . . . . . . 78Installed dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Logano plus SB815See Logano plus SB815 gas fired condensing boiler

Logano plus SB815 LNSee Logano plus SB815 gas fired condensing boiler LN

Logano plus SB825L & SB825L LNBoiler house dimensions . . . . . . . . . . . . . . . . . . . . . . . 78Installed dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Logano plus SB825L and SB825L LNgas fired condensing boilersTransport dimensions . . . . . . . . . . . . . . . . . . . . . . . . . 75

Logano plus SB825L gas fired condensing boilerCombustion specification . . . . . . . . . . . . . . . . . . . 44, 45Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26, 27Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18, 19Equipment summary . . . . . . . . . . . . . . . . . . . . . . . . . 10Features and characteristics . . . . . . . . . . . . . . . . . . . . . 5

Keyword index13 Appendix

96

13


Appendix

Flow safety line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Operating conditions . . . . . . . . . . . . . . . . . . . . . . . . .48Principle of operation . . . . . . . . . . . . . . . . . . . . . . . . .10Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22, 23

Logano plus SB825L LN gas fired condensing boilerCombustion specification . . . . . . . . . . . . . . . . . . .46, 47Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26, 27Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20, 21Equipment summary . . . . . . . . . . . . . . . . . . . . . . . . . .10Features and characteristics . . . . . . . . . . . . . . . . . . . . . .5Flow safety line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Operating conditions . . . . . . . . . . . . . . . . . . . . . . . . .48Principle of operation . . . . . . . . . . . . . . . . . . . . . . . . .10Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24, 25Transport dimensions . . . . . . . . . . . . . . . . . . . . . . . . .75

Logano S815See Logano S815 boiler

Logano S815 LNSee Logano S815 LN boiler

Logano S825L boilerBoiler house dimensions . . . . . . . . . . . . . . . . . . . . . . .77Combustion specification . . . . . . . . . . . . . . . . . . .40, 41Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26, 27Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12, 13Equipment summary . . . . . . . . . . . . . . . . . . . . . . . . . .10Features and characteristics . . . . . . . . . . . . . . . . . . . . . .5Flow safety line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Installed dimensions . . . . . . . . . . . . . . . . . . . . . . . . . .77Operating conditions . . . . . . . . . . . . . . . . . . . . . . . . .48Principle of operation . . . . . . . . . . . . . . . . . . . . . . . . .10Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16Transport dimensions . . . . . . . . . . . . . . . . . . . . . . . . .75

Logano S825L LN boilerBoiler house dimensions . . . . . . . . . . . . . . . . . . . . . . .77Combustion specification . . . . . . . . . . . . . . . . . . .42, 43Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26, 27Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14, 15Equipment summary . . . . . . . . . . . . . . . . . . . . . . . . . .10Features and characteristics . . . . . . . . . . . . . . . . . . . . . .5Flow safety line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Installed dimensions . . . . . . . . . . . . . . . . . . . . . . . . . .77Operating conditions . . . . . . . . . . . . . . . . . . . . . . . . .48Principle of operation . . . . . . . . . . . . . . . . . . . . . . . . .10Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17Transport dimensions . . . . . . . . . . . . . . . . . . . . . . . . .75

Low loss header line . . . . . . . . . . . . . . . . . . . . . .58, 64

MMaintenance . . . . . . . . . . . . . . . . . . . . . . . . . .5, 48, 58

NNeutralising systemEquipment level . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92Neutralisation duty . . . . . . . . . . . . . . . . . . . . . . . . . . 91Neutralising medium . . . . . . . . . . . . . . . . . . . . . . . . .92Positioning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91Pump rate diagram . . . . . . . . . . . . . . . . . . . . . . . . . . .92

Noise attenuationBoiler foundation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87Boiler mounts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86Burner silencer hood . . . . . . . . . . . . . . . . . . . . . . . . . 86Flue gas silencer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

OOperating conditions . . . . . . . . . . . . . . . . . . . . . . . 48

RRaising the return temperature . . 8, 58, 65, 66, 69, 84

Regulations and requirements . . . . . . . . . . . 48, 49, 76

Return temperature sensor . 62, 66, 68, 70, 71, 72, 73

SSafety equipmentBoiler safety equipment assembly . . . . . . . . . . . . . . . . 80Heat exchanger safety assembly . . . . . . . . . . . . . . . . . 61Maximum pressure valve . . . . . . . . . . . . . . . . . . . . . . 80maximum pressure valve . . . . . . . . . . . . . . . . . . . 79, 83Minimum pressure valve . . . . . . . . . . . . . . . . . . . . . . 79Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Safety rail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Safety valve . . 10, 26, 61, 62, 63, 71, 72, 73, 74, 82, 83

Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Sensible heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Standard delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Standard efficiency . . . . . . . . . . . . . . . . . . . . . . . . 8, 35

Standby loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34, 35

System examplesControl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Dirt traps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Domestic hot water heating . . . . . . . . . . . . . . . . . . . . 59Heating circuit pumps . . . . . . . . . . . . . . . . . . . . . . . . 58Logano plus SB825L gas fired condensing boiler 71, 72, 73, 74Logano S825L boiler . . . . . . . 65, 66, 67, 68, 69, 70, 73Single boiler system . . . . . 62, 65, 66, 67, 68, 71, 72, 74Two-boiler system . . . . . . . . . . . . . . . . . . 63, 69, 70, 73

System temperatureBoiler efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Flue gas temperature . . . . . . . . . . . . . . . . . . . . . . . . . 37

TTransport dim. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

WWalk-on boiler cover . . . . . . . . . . . . . . . . . . . . . . . . 89

Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48, 58

Water quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

97

Appendix 13


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■ BelgiumBuderus VerwarmingChauffage N.V./S.A.Ambachtenlaan 42AB-3001 LeuvenTel.: 00 32-16-40 30 20Fax: 00 32-16-40 04 [email protected]

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Documents

Issue 06/2005 Technical Guide - buderus.dk · 3 Contents Technical Guide Logano S825L / S825L LN boilers and Logano plus SB825L / SB825L LN gas fired condensing boilers – 06/2005