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Tech 3 - Harry DemetruliasTechnical Session from the 2006 ASHRAE Region VI CRC
Citation preview
Temperature Controls“Why Don’t They Work?
Harry Demetrulias
1. Many Controls Contractors ARE Crooks!
2. Mechanical Design Problems
3. Mechanical Installation Problems and
Equipment Malfunction
4. Operator Errors and Overrides
5. Controls Installations: Misapplied Field
Devices, Sensor Locations, Lack of
Calibration, and PID Loop Tuning
Top 5 Reasons
Control Systems
Don’t Work
Blame the OwnersBlame the Owners
““Owners are too demanding and Owners are too demanding and
unrealistic in their cost expectationsunrealistic in their cost expectations””
Lower!Lower!
How How
Low?Low?
Blame The Blame The
ArchitectsArchitects
““Architects are too Architects are too
focused on aesthetics, focused on aesthetics,
and do not allow and do not allow
adequate space for adequate space for
building systems: building systems:
Mechanical Rooms and Mechanical Rooms and
Interstitial SpaceInterstitial Space””
Blame the GeneralsBlame the Generals
General Contractors punch out projects General Contractors punch out projects
without scheduling adequate time for without scheduling adequate time for
StartStart--up, Checkout, Test & Balance, and up, Checkout, Test & Balance, and
Commissioning activitiesCommissioning activities
““Mechanical Mechanical
Engineers Engineers
Overworked Overworked
and and
Underpaid!Underpaid!””
Blame the Blame the
EngineersEngineers
Blame the SuppliersBlame the Suppliers
““Equipment Suppliers Equipment Suppliers
Just Just
SELL STUFF SELL STUFF
and Donand Don’’t Support it!t Support it!””
Blame the BalancerBlame the Balancer
““Do you really trust Do you really trust
those Test & Balance those Test & Balance
Reports?Reports?””
““Should we blame those Should we blame those
Design/Build Mechanical Design/Build Mechanical
Contractors?Contractors?
Requires Professional
COLLABORATION
FingerFinger--pointing pointing
is easyis easy
Working toward Working toward
SolutionsSolutions
Function or Function or
Malfunction is Malfunction is
without exception without exception
a collaborative a collaborative
effort between effort between
Consultant, Consultant,
Mechanical Mechanical
Contractor, Contractor,
Controls Controls
Contractor and Contractor and
Facility Facility
Operations.Operations.
Temperature Control is simple.
Building Automation is complex…
How can we promote How can we promote
Collaboration?Collaboration?
Delivering Truly Integrated Building Systems To Owners
Requires Collaboration
- Engineers - Controls Contractors - Mechanical Contractors
- Equipment Suppliers - Facility Operations
When Temperature Control When Temperature Control
Becomes ComplicatedBecomes Complicated
•• Economizer ModeEconomizer Mode
•• Variable Volume/FlowVariable Volume/Flow
•• Dynamic ResetsDynamic Resets
•• WarmWarm--up/Coolup/Cool--down Modesdown Modes
•• Building Pressurization ControlBuilding Pressurization Control
•• Smoke Control Smoke Control
••UnderfloorUnderfloor SystemsSystems
•• IAQIAQ
•• Load Shedding Programs Load Shedding Programs
••TOD SchedulingTOD Scheduling
•• PRAC SelfPRAC Self--TuningTuning
•• Integrations to 3Integrations to 3rdrd PartiesParties
•• Validated SystemsValidated Systems
Controls ContractorControls Contractor’’s s
Perspective: Perspective:
The Consultant as The Consultant as
PROBLEMPROBLEM……or or
SolutionSolution
Market Pressure
& the Design Community
• Hyper-competition
• Below Market Design Fees
• Allotted Billable hours for
quality designs and
specifications
• Lack of onsite Project
Engineering
• Reliance on draftsmen to
incorporate last minute
changes
• Addenda Ad Infinitum
The Key:Publish Quality
Documents
⌫ Installation is only as good as the design
⌫ Errors on P&S result in problems in the field
⌫ Malfunction begins in the mind of the designer
⌫ Unedited Master Specifications ⌫ Lower engineering
cost but…
⌫ Many Change Orders/retrofit corrections
• “DDC controllers shall be BACnet. Lonmark AND N2
Open Protocol compliant…”
• “Acceptable manufacturers are Alerton, Andover, Delta,
Honeywell, Invensys, Johnson Controls, Siemens,
Staefa Controls, Trane, or approved equal.”
Example #1: Nonspecific Specifications
Example #2:
Healthcare project…
LOWEST TOTAL COST OF OWNERSHIP
2. Electric, Electronic, and DDC Systems:
a. Alerton Technologies, Inc.
b. Andover Controls Corp.
c. Automated Logic Corporation.
d. Auto-Matrix, Inc.; Auto-Flow Division.
e. CSI Control Systems International, Inc.
f. Danfoss Automatic Controls.
g. Delta Controls Inc.
h. EDA Controls Corp.
i. Electronic Systems USA, Inc.
j. G C Controls, Inc.
k. Honeywell, Inc.; Home & Building Control.
I. Impact Energy Controls Corp
m. Johnson Controls, Inc.; Controls Group.
n. KMC Controls/Kreuter Manufacturing Company.
o. Landis & Staefa, Inc.
p. Luwa Bahnson Inc.
q. McQuay Intemational.
r. Neles-Jamesbury.
s. Pneuline Controls Co.; National Energy Controls Corp.
t. Scientific-Atlanta, Inc.; Control Systems Div.
u. Siebe Environmental Controls; Barber-Coleman/Robertshaw
Products
v. Solidyne Corp.
w. TCS/BASYS Controls
x. Teletrol Systems Inc.
y. Trane Co. (The); North American Commercial Group.
z. Triangle MicroSystems, Inc.
aa. Uni-Line North America; Robertshaw Division.
3. Systems must interface seamlessly with existing front end control
system
Anyone Anyone
Missing?Missing?
7
N C
DPR-O
N O
N C
EA
OA
RA
RA-T
RA-H
MA-T
SA
RA-SD
(Div. 16)
SUPPLY
RETURN
N O
CLG-O
C
C
PFILT-A
Set @ 1"
H LLT-ALM
(38 Deg F)
SA-P
H L
SA-THUM-HL
FFILT-A
Set @ 1"
H L
HSP2-A
Set @4"
H L
SA-SD
(Div. 16)3
4
4
10-27
HUM-O
VSD
RA-F1
VSD
RA-F2
N C
RF1ISO-S
N C
RF2ISO-S
N C
SF1ISO-S
N C
SF2ISO-S
VSD
SF-F1
VSD
SF-F2
N C
HUM-VLV
STM
8
10
9
HSP1-A
Set @4"
H L
0-7.5"
Damper Control: Damper Control: When the unit is commanded on, the When the unit is commanded on, the
outside air damper shall fully open. When the unit is outside air damper shall fully open. When the unit is
commanded off, the outside air damper shall close. The commanded off, the outside air damper shall close. The
exhaust damper shall remain closed and the mixed air exhaust damper shall remain closed and the mixed air
damper shall remain open.damper shall remain open.
Discharge Air Temperature Control:Discharge Air Temperature Control: When the unit is When the unit is
commanded on, the outside air damper, return air damper, and commanded on, the outside air damper, return air damper, and
relief air damper will be open. Discharge temperature sensor SArelief air damper will be open. Discharge temperature sensor SA--
T through the DDC Controller will modulate the cooling coil 2T through the DDC Controller will modulate the cooling coil 2--way way
control valve CLGcontrol valve CLG--O to maintain setting. The discharge air O to maintain setting. The discharge air
temperature will be controlled to maintain a 55temperature will be controlled to maintain a 55°°F F setpointsetpoint..
Example #3:Example #3:
Specify SPECIFICS…
LOWEST TOTAL COST OF OWNERSHIP
Specify limited qualified
bidders that are suitable for
• market type
• product application
• contractor expertise
Balance First Cost with Operating CostBalance First Cost with Operating Cost
⌫ Write Specifications that refer to other sections and technologies.
⌫ Detail the responsibilities
⌫ Furnished by…
⌫ Installed by…
⌫ Wired by…
IT NETWORK
VIDEO-ON-
DEMAND
HOTEL OPERATING
SYSTEM
PABX
PAGING
CMMS
15 BUILDING SERVICES
CCTV SECURITY
CENTRAL PLANT
LIGHTING
ELEVATOR
FIRE
BAS Cross-Referencing
Include at Minimum: Include at Minimum:
Flow DiagramsFlow Diagrams
Point Charts Point Charts
SequencesSequences
Sequence of OperationSequence of Operation
EXHAUST SYSTEM: EFEXHAUST SYSTEM: EF--1 and EF1 and EF--22
Isolation Exhaust Fans EFIsolation Exhaust Fans EF--1 and EF1 and EF--2:2:
On command from the BAS, the fans shall start. If On command from the BAS, the fans shall start. If
for any reason the fan status does not match its for any reason the fan status does not match its
commanded value, an alarm will be generated.commanded value, an alarm will be generated.
ISOLATION ROOM MONITORSISOLATION ROOM MONITORS
System Description:System Description:
The Isolation Rooms shall be monitored by a Space The Isolation Rooms shall be monitored by a Space
Pressure Monitor as described in controls Pressure Monitor as described in controls
specification at minimum and shall generate an specification at minimum and shall generate an
alarm at the BAS upon general alarm or deviation alarm at the BAS upon general alarm or deviation
from space pressurization from space pressurization setpointsetpoint ((adjadj). ).
P.E. Professional
Enforcer⌫ Enforce your
specifications
⌫ Guard against cheating in hyper-competitive market
⌫ Get involved in checkout, functional testing and commissioning
⌫ Specify Commissioning Expectations
⌫ Review Checkout Sheets
⌫ Verify that field devices match the specification
10. Delete lab VAV: Constant volume labs
9. Delete DDC from FCUs
8. Delete SAT Sensors on VAV w/RH
7. Delete DPs across filter racks
6. Delete interfaces to Chillers, Boilers and VFDs
5. Delete AFMS from AHUs SA/RA/OA
4. Delete VAV zones and combine multiple zones
3. Delete Custom Controls on RTUs in lieu of
packaged
2. Delete RH Coils in lieu of Cooling Only VAV
1. Delete DDC from VAV/CAV terminals
Resist DeResist De--Value EngineeringValue Engineering
Technology
⌫ Technology is more affordable than ever.
⌫ But it has made building controls more complicated for Specifying Engineers
Capabilities of Technology
Cost of Technology
19901990 20062006
Get Help from Your
Local Controls Experts
and Sales Engineers
The System Selection Tool was
designed to help specifying engineers
quickly develop detailed, accurate
plans and specifications for heating,
ventilation and air conditioning (HVAC)
Summary: A New
Level of
Engineering Value
⌫ Step 1 Publish Quality Documents
⌫ Step 2 Resist De-Value Engineering
⌫ Step 3 List Qualified Bidders
⌫ Step 4 Enforce Specifications
⌫ Step 5 Get Support and Consultation from Reputable Controls Companies
$
Design/Build and Value Engineering
Exploiting Owner’s Lowest First Cost Demands?
Less quality in More value out
Less quality in More value out
Hyper/Competitive Market and the D/B Model:Contractors Control Design
- Reliance on Equipment Suppliers for TC- Packaged systems w/canned programs
“We can do it
cheaper and
faster!”
Hard Bid/Design/Build
Can this building be fixed?
Slam it in Commission it later
Problem: Mechanical Design & Controls Issues
– Building Pressurization Problems
– Toggling RTU Modes
– Uneven Underfloor Distribution
– Overly cool interior zones
– Overly warm exterior zones
– No humidity control
– Energy Hog—could not qualify for Energy
Star rating
Symptoms
Building # 1
D/B Debacle
ASHRAE Temperature Controls: Temperature Controls: Temperature Controls: Temperature Controls: ““““Why DonWhy DonWhy DonWhy Don’’’’t They Work?t They Work?t They Work?t They Work?””””
Problem: Mechanical Design & Controls Issues
– VAV w/General Exhaust System
– No trunks to distribute UFS
– Improperly placed pressure sensing devices
– No calibrated primary T/H devices
– Cooling mode problems
– Dueling PID Loop Control on RTU
– Inability to alter or augment canned RTU
program—limitations
ASHRAE
Causes
Building # 1
D/B Debacle
Temperature Controls: Temperature Controls: Temperature Controls: Temperature Controls: ““““Why DonWhy DonWhy DonWhy Don’’’’t They Work?t They Work?t They Work?t They Work?””””
Problem: Mechanical Design & Controls Issues
– Hire a COMMISSIONING AGENT!
– Add return fans
– Add trunks to distribute UFS
– Relocate pressure sensing devices
– Calibrate primary T/H devices
– Replace misapplied DDC hardware
– Reprogram and recommission
– Work with commissioning agent
ASHRAE
Solutions
Building # 1
D/B Debacle
Temperature Controls: Temperature Controls: Temperature Controls: Temperature Controls: ““““Why DonWhy DonWhy DonWhy Don’’’’t They Work?t They Work?t They Work?t They Work?””””
⌫ Manual Control
⌫ Automation does not work well in the “HAND”position
““ItIt’’s always a s always a
Controls Controls
Problem!Problem!””
……often times it isoften times it is……
The Controls Contractor as Part of the The Controls Contractor as Part of the
SolutionSolution……
Absorption
Pumping & VFDs
Generators
Lighting
Fire Alarm
Boilers
Fume Hood
Chiller
Power
Fan Systems
Surgical Suites
⌫ Today’s Technology is less expensive
⌫ But the Labor is not
⌫ Margin Expectations Continue to Rise
⌫ Competition is driving the quality out
Controls Industry Controls Industry
as the Problem:as the Problem:
⌫ Person at Metasys workstation
⌫ Today’s Technicians often know computers but lack understanding of basic mechanical systems
⌫ Application Engineering & Commissioning Challenges
⌫ Decreased skill sets in controls software engineering
⌫ Protocols do NOT control buildings
⌫ Software illiteracy
⌫ Reliance on automated processes
⌫ Lack of Quality Management processes
⌫ What is Commissioning?
Building Technology Has Complicated Simple Temperature
Controls
⌫ Comfort
⌫ Lighting
⌫ Security
⌫ Scheduling
⌫ Access control
⌫ Fire safety⌫ Communications
⌫ Fuel conservation
⌫ Power load management
⌫ Maintenance management
COMPLEXITY
Value AddedServices?
⌫ Phase 1 Low First cost
⌫ Phase 2 Prices just went up!
⌫ Phase 3 Delivering less value over time
Controls Industry Controls Industry
as the Problem:as the Problem:
Solution 1:
Can we consider a new
Level of Value?
⌫ Phase 1 Low First cost
⌫ Phase 2 Open Book Pricing
⌫ Phase 3 Pricing Agreements
⌫ Phase 4 Meet the Specifications
⌫ Phase 5 Exceed Customer Expectations
Solution 2: Expert Services
⌫ Provide support and educational services to the engineering community
⌫ Offer design review services and provide input on sequences, points lists and specifications
⌫ Review Bid Documents and write good clear RFIs early in the process
Customer & Design Team
Controls HVAC Fire
Security
Lighting
Power Mgmt
Mechanical Contractor
Electrical Contractor
⌫ Windows⌫ Raised Floor⌫ etc
GeneralGeneral Behave more like consulting experts, less like the proverbial Crooks
Be professional and deliver on Performance Specifications
Submit proper checkout and commissioning documentation to Consultants
Make Buildings Work
Solution 3:
Deliver as Promised
Quality Assurance…
⌫ Apply ASHRAE Standards
⌫ Due diligence on installations and checkout practices
⌫ Tune loops and set up trends during checkout and commissioning
⌫ Work with Designers as fellow engineers, not combative contractors
⌫ Review Checkout Sheets
⌫ Verify that field devices match the specification
Working Together Working Together
we can deliver we can deliver
better design and better design and
construction construction
projects and the projects and the
High Performance High Performance
Buildings that Buildings that
Owners are Owners are
paying for.paying for.
Temperature Controls“Why Don’t They Work?
Q & A
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