DIVISION 23 HEATING, VENTILATING AIR CONDITIONING (HVAC) HVAC... · 2020. 11. 16. · DIVISION 23 – HEATING, VENTILATING & AIR CONDITIONING (HVAC) ... The purpose of these design

UMass HVAC Standards Issued 9/4/20

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DIVISION 23 – HEATING, VENTILATING & AIR CONDITIONING (HVAC) TABLE OF CONTENTS Section 23 0000 General ................................................................................................................ 2 Section 23 0130 HVAC Air-Distribution System Cleaning ............................................................. 12 Section 23 0593 Testing, Adjusting, and Balancing ...................................................................... 13 Section 23 0700 Insulation ........................................................................................................... 14 Section 23 0800 Commissioning ................................................................................................... 16 Section 23 0900 Controls .............................................................................................................. 16 Section 23 2100 Piping ................................................................................................................. 29 Section 23 2123 Hydronic Pumps ................................................................................................. 33 Section 23 2500 HVAC Water Treatment ..................................................................................... 34 Section 23 3100 HVAC Ducts and Casings .................................................................................... 36 Section 23 3700 Air Outlets and Inlets ......................................................................................... 38 Section 23 5200 Boilers ................................................................................................................ 39 Section 23 5700 Heat Exchangers For HVAC ................................................................................ 39 Section 23 6313 Air Cooled Refrigerant Condensers .................................................................... 39 Section 23 6400 Chillers ............................................................................................................... 39 Section 23 6500 Cooling Towers .................................................................................................. 40 Section 23 7300 Air-handling Units .............................................................................................. 41 Section 23 8100 Terminal Units .................................................................................................... 43 Section 23 8413 Humidifiers ......................................................................................................... 44


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SECTION 23 0000 GENERAL PURPOSE The purpose of these design standards is to foster the health, wellbeing, and productivity of the University’s students, faculty, staff and visitors by providing an optimum indoor environment with minimum global environmental impact. To this end equipment and systems must be both performance effective and cost effective on a life cycle basis, with an emphasis on maintainability and energy efficiency. While maintaining the responsibility of the designer or installer and encouraging innovation, this document seeks to clarify our priorities and assemble the best of our knowledge and experience to date in these matters.

System design and equipment selection shall be determined by life cycle cost analysis including first, operating, and maintenance costs. O&M costs are of particular concern due to the long life cycles and limited maintenance resources of installed equipment.

Central systems are preferred due to their typically higher system efficiencies, diversification of loads, and lower maintenance requirements. This typically entails equipment (chillers, pumps, cooling tower, air handling units, etc.) located on rooftops or in basement and/or penthouse mechanical rooms.

Make use of existing building systems wherever possible, i.e. steam, air, chilled water, hot water. Prior to the start of design, confirm existing conditions with the UMass project manager, Physical Plant facilities engineers, building technicians, on-site verification, and use of the extensive UMass documentation library. As part of design proposal development and conceptual design phases, the designer and UMass project manager shall discuss the level of existing system investigation and analysis that is warranted based on the potential impact of the new systems and design fee budget available. The outcome of these discussions shall be documented by the designer in the Owner’s Project Requirements.

When connecting to existing systems, the actual operating conditions, (temperatures, volumes, etc.) should be used, not the design values shown on the as-built drawings. Subsequently, some amount of communication with building technicians and field verification of actual operating conditions is expected. Time of year availability (i.e. seasonal utilities) and variations in seasonal setpoints should be considered with equipment selections and capacities.

Energy and fuel sources: For buildings within the main campus of UMass Amherst, steam is provided from our central cogeneration plant from a combination of natural gas, LNG, and fuel oil supplies. Use of this heating source either directly or indirectly is generally preferred due to its economy, although in some cases efficient heat pump heat should be considered. For many hours of the year our marginal electrical supply comes from the local utility with hourly pricing, and peak monthly and annual electrical demand is an important consideration. Electric resistance heating systems are not preferred and highly discouraged.

Centralized chilled water systems are the preferred means for providing process cooling for equipment, such as lab equipment, and for HVAC needs. If chilled water systems are used for


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process cooling or other year-round cooling applications, then provision for economical winter chilling should be provided.

Utilize ASHRAE 1% weather data from the Chicopee weather station for design load calculations, unless otherwise directed by the UMass project manager.

Ventilation systems shall be designed in accordance with the latest version of ASHRAE 62.1. In addition, projects exceeding 10,000 gsf with a new central ventilation system shall include a Flush Out Period per the current version of the USGBC LEED program, independent of whether the project is seeking LEED accreditation.

Unoccupied areas, such as storage, mechanical and electrical rooms, should be ventilated and heated to 50°F for temperature control. Considerations for cooling systems (by ventilation or mechanical means) should be made if room temperatures consistently exceed 85°F.

Design systems to maximize flexibility to accommodate future changes, renovations and repairs. In consultation with the project manager and where feasible, include additional capacity (typically 10% to 20% above peak design) and accommodate space to add additional components. Minimize the number of individual systems but provide cross connections for redundancy wherever possible. Provide N+1 redundancy for the major components of all systems serving critical needs. Critical needs would typically include animal care facilities, data centers, and large laboratories.

At the completion of any renovation project, all necessary components and piping shall be insulated.

Design and construction coordination drawings between trades are required.

OWNER’S PROJECT REQUIREMENTS For all projects, independent of size, designers shall work with the Owner to specifically document the owner’s project requirements (OPR). For projects with an engineering design fee exceeding $10,000, acknowledgment of the OPR shall be formalized in written form. The OPR document shall be included in the basis of design report for review and confirmation by the Owner, and shall be updated and filed with the project closeout documents.

The OPR shall include as many of the following as are applicable. Note that in many cases, the owner’s requirements will align with the requirements in these standards and can be carried over to the OPR from this document. For all items, however, the Owner shall have the opportunity to customize the requirements to fit the specific scope and circumstances of the project.

• Schedule and budget • Owner’s directives • Project overarching goals • Programming needs • Scope boundaries • Owners standards/guidelines to be considered during design • Space Based Design Criteria (see below) • Documentation


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• Operational Goals (e.g. annual energy costs, equipment uptime) • Specific commissioning requirement • Specific training requirements • Warranty issues • Constructability • Quality of materials and construction • Longevity, durability, and maintainability • Safety (structural, fire, accident, security) • Aesthetics • Sustainability and environmental impact • Adaptability

The OPR shall be reviewed and adjusted as necessary for each project, but suggested initial values are given below.

SCHEDULE Space Type Suggested Preliminary Value

Lab Available 24/7 with occupancy sensors for standby mode

Classroom Occupied 7:00 am to 8:00 pm on weekdays only

Office Occupied 7:00 am to 5:00 pm on weekdays only

Mechanical/Electrical Room No schedule

Storage No schedule

Data Center/IDF Closet No schedule

SPACE TEMPERATURE Space Type Suggested Preliminary Value

Lab 72 °F ± 1 °F (occupied) with occupant adjustment via thermostat

72 °F ± 3 °F (standby) with occupant adjustment via thermostat

62 °F (unoccupied heating) / 78 °F (unoccupied cooling)

Classroom 72 °F ± 2 °F (occupied) with occupant adjustment via thermostat



Office 72 °F ± 2 °F (occupied) with occupant adjustment via thermostat



Common Areas 72 °F ± 2 °F (occupied) with no occupant adjustment via thermostat

72 °F ± 4 °F (standby) with no occupant adjustment via thermostat


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Mechanical/Electrical Room 60 °F (heating) / 80 °F (cooling, if applicable, or room exhaust enable)

Storage 60 °F (heating only)

Data Center/IDF Closet 60 °F (heating, if applicable) / 76 °F (cooling)

SPACE HUMIDITY Space Type Suggested Preliminary Value, where achievable

Lab 30% RH (minimum) / 60% RH (maximum)

Classroom 30% RH (minimum) / 60% RH (maximum)

Office 30% RH (minimum) / 60% RH (maximum)

Mechanical/Electrical Room No requirement

Storage No requirement

Data Center/IDF Closet 30% RH (minimum) / 60% RH (maximum)

INDOOR NOISE LEVELS Indoor noise level requirements shall be specifically selected by the acoustical consultant, in consultation with the UMass team of stakeholders, if an acoustical consultant is included in the project team. The following are intended as preliminary suggestions for consideration by the project team.

Space Type Suggested Preliminary Value

Lab NC 35

Classroom NC 35

Office NC 35

Auditorium NC 25

Mechanical/Electrical Room No requirement

Storage NC 40

Data Center/IDF Closet NC 40

OUTDOOR NOISE LEVELS Space Type Suggested Preliminary Value

At Property Line 60 dBA

Next to Outdoor Equipment at Grade

60 dBA at the closest adjacent building

Next to Outdoor Equipment on Roof

No requirement so long as indoor noise levels are not exceeded in surrounding spaces


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AIR CHANGE RATES Space Type Suggested Preliminary Value

Lab 6 – 10 ACH typical depending on chemicals used, but confirm in writing with EH&S (occupied)

2 – 6 ACH typical depending on chemicals used, but confirm in writing with EH&S (unoccupied)

Non-Lab No requirement

BASIS OF DESIGN REPORT For all projects with an engineering design fee exceeding $10,000, designers shall provide a written basis of design (BOD) report to the Owner for review and comment prior to proceeding with design development or construction documents. The BOD represents a summary narrative of how the designer intends to achieve the OPR.

The BOD report shall include the following:

1. Confirmation of the owner’s project requirements (OPR). The designer shall comment on the feasibility of achieving each of the owner’s requirements and shall provide commentary as to the limiting factors if one or more requirements are not likely to be met. When tradeoffs exist among requirements, the designer shall provide a description of the impact of a given decision on each of the applicable requirements.

2. Specific numerical inputs and assumptions used for load calculations and equipment sizing (e.g. design outside air dry bulb and wet bulb temperature, design number of occupants, design lighting power density for cooling load purposes).

3. Assumptions and/or recommendations for redundancy, excess capacity, and energy resiliency (e.g. backup power, standalone operation upon loss of communication).

4. Proposed equipment type, sizing, BOD manufacturer and model, and recommended options for all major equipment being provided as part of the project. Additionally, provide a summary of alternative system types and/or manufacturers for the Owner’s consideration with a written discussion of the relative strengths and weaknesses of the various options. If requested by the Owner, provide budgetary cost estimates for each of the options under consideration.

5. Preliminary recommended location of all major equipment and a discussion of any anticipated challenges, obstacles, or other coordination items.

6. Summary of the type, size, condition, and controls of existing equipment that will be reused as part of the project.

7. Plain English narrative (i.e. not in specification language) of the scope of the project. Include in the narrative a preliminary recommended approach for removal of old equipment and rigging of new equipment, where applicable. For example, review


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whether proposed equipment can fit through doorways or cranes can access rooftop equipment from available roadways.

8. Plain English narrative of the intended controls strategies.

9. Summary of information requests to the Owner and/or other stakeholders required to complete the design.

10. Summary of out of scope work, scope to be designed in future phases, and/or scope to be addressed in future project phases, if applicable.

LIFE CYCLE COST ANALYSIS Designers are specifically instructed to design systems that minimize life cycle cost, calculated in terms of lifetime cost net present value, to the extent possible given the OPR and allowable schedule for the project.

Unless otherwise directed by the UMass Project Manager, for any project with an engineering fee exceeding $10,000 and where multiple feasible system types are permitted by these Standards, the designer shall prepare a life cycle cost analysis comparing the various system types under consideration. The life cycle cost analysis shall occur during the schematic design and/or basis of design phase.

Life cycle cost calculations shall include the following factors.

• First cost • Utility rebates and incentives • Annual energy cost • Annual or on-going maintenance cost • Expected equipment useful life • Replacement costs, if applicable (e.g. if Pump-1 is expected to last 15 years and Pump-2

is expected to last 20 years, include the estimated replacement cost for Pump-1 in Year 16)

Life cycle cost analyses shall be limited to only the applicable scope being considered. For example, if multiple chiller technologies are being compared, the life cycle cost analysis can be limited to the chilled water plant and the remainder of the project scope need not be estimated as part of this effort.

Utilize the construction manager for the project, if available, to obtain first cost estimates for the various options. Alternatively, utilize UMass’ resources if possible. If neither is available, the designer shall work with the primary equipment vendors to obtain budget pricing and shall estimate other components of the project cost, such as piping, ductwork, and controls, using accepted industry resources, such as RS Means.

Energy cost estimates shall factor in both nominal and part load equipment performance data.

Maintenance costs shall include any warranty costs, annual service contract costs from vendors, specific component replacement costs (e.g. air filters), and estimated UMass maintenance labor costs. Consult with the UMass Project Manager for help compiling this data.


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Consult with the UMass Project Manager to confirm the most up to date values of the following parameters, but these values may be used as a starting point.

• Average electricity unit cost – $0.10/kWh blended • Average steam unit cost - $20/Mlb steam • Average natural gas unit cost - $9.87/MMBtu • Average water/sewer unit cost - ask UMass Project Manager • Average electric utility incentive - ask UMass Project Manager • Average natural gas utility incentive - ask UMass Project Manager • Utility cost inflation – 1% per year • Maintenance labor cost - $65.00 per hour • Maintenance cost inflation – 2% per year for costs not locked in by service contract • Discount rate – 10% • Life cycle cost analysis duration – 20 years

Refer to the following link for more information: https://www.mass.gov/doc/designers-procedures-manual/download

ENERGY CONSERVATION In addition to applicable State and local codes, systems and equipment will be designed to be energy efficient and at a minimum shall be designed in accordance with the latest version of ASHRAE 90.1. Specific energy efficiency and greenhouse gas reduction goals, in conjunction with the University’s long-term greenhouse gas reduction and carbon neutrality goals, shall be discussed and set as part of developing the Owners Project Requirements on each project and in many cases may exceed the requirements of the latest version of ASHRAE 90.1.

Designers shall also quantify and discuss the impact on campus electrical and steam distribution demands with the UMass Project Manager and representatives from the Physical Plant assigned to the project. Where possible, demand management features shall be incorporated into the design to provide future flexibility for University Operations.

Design equipment and controls for the different types of occupancy and schedules within the building. Provide setback temperature controls, with manual override, for nights, weekends and holidays. Where setback cannot be accomplished, reduced flow operation should be provided.

Each project should be analyzed for the recovery of usable energy, regardless of Code requirements. The Engineer shall perform an economic analysis to determine the appropriateness of energy recovery systems.

All ventilation systems shall consider whenever possible the capacity to use 100% outside air to meet cooling and ventilation requirements with economizer control during mild to medium seasonal demands.

Part and variable load control shall be designed for all systems unless otherwise approved by the UMass project manager. Variable frequency drives and/or ECM motors should be the basis of design for control of motor speed in variable flow systems.


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MAINTAINABILITY The University prefers direct drive fans rather than belt drive fans

Specify rotating equipment for 200,000-hour L50 bearing life, or more if readily available.

Equipment should be located indoors and outside of occupied spaces wherever possible.

Designs will accommodate routine maintenance procedures (for example filter or belt changes) with quick and safe accessibility.

Limit need for above ceiling access, for example utilize filter grilles for FCUs rather than above ceiling filter access, and locate all control panels, especially supervisory control panels, below ceilings unless they are unit mounted. Show location of control panels serving multiple units on the design documents.

Provide adequate free space (40% suggested) within ceiling spaces, riser chases and soffits to account for future growth and modifications.

Designers shall prepare coordination drawings between trades, and accommodate design phase review sessions with UMass facilities staff focused on maintainability of the proposed equipment and locations. Contractors shall also prepare coordination drawings between trades, and offer construction phase review sessions with UMass facilities staff to confirm design decisions made focused on maintainability.

Provide clearances and accessibility to optimize maintenance. Design for floor access whenever possible. Assure that coils, heat exchangers or tubes, motors, pumps, fans, valves, and dampers and damper actuators can be accessed, diagnosed, and replaced. Include isolation valves and unions for all hydronic components including control valves. Provide clearly marked isolation valves for risers, mains, and mechanical rooms. Provide inspection capability for coils, control dampers and pitot tubes with access doors or other removable components.

Exhaust fans shall be located on the roof. Exhaust motors shall be located to allow access for maintenance. Designers shall locate rooftop equipment at least 10 feet away from the roof edges if possible, to avoid installation of rooftop safety railing, harness, or other anchor points.

Avoid locating maintenance requiring HVAC components over lab benches, desks, etc. which would preclude simple ladder access.

Air heating and cooling coils shall be designed with depths, fin spacing, and access sections to allow effective cleaning.

DEMOLITION Designers shall specify that duct or pipe branches be demolished back to the nearest active point of connection. Do not leave unused, capped branches.

PREFERRED SYSTEM TYPE BY SPACE TYPE HVAC system design is subject to many constraints. Existing or new building construction materials or space, availability of steam, hot water, chilled water, budget, particular energy or performance goals, etc. The following descriptors attempt to describe system preferences in


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various applications. It should be taken as a starting point in the design process, not as absolute requirements.

Elevator Machine Rooms – wherever possible, cooling systems with economizers shall be installed outside of rooms to provide maintenance without room access. Stairwells do not fit category.

Laboratory Spaces – air valves controlling each supply and exhaust terminal, including fume hoods and snorkel exhausts, with duct-mounted reheat coils for temperature control. Include supplementary air conditioning systems, such as fan coil units, with recirculation air only, for labs with high sensible cooling loads. Fan coil units, when installed should be the first mode of zone cooling to limit the increase of conditioned, 100% outdoor air. Central air handling unit shall have chilled water cooling, hot water glycol heating with coil pump, and provide 100% outside air with heat recovery from the exhaust air stream. Provide VFDs for supply fans with static pressure control. Air valves shall be low pressure type with true high turndown airflow metering, similar to Accuvalve. Air valves shall provide direct reading of airflow and utilize direct control output from the BAS, hardwired. The BAS will perform volumetric offset for lab pressure control and provide temperature control. General exhaust air valves, if used, shall be full shutoff type. Fume hood control can be local face velocity display with BACnet MS/TP integration along with separate wired air flow signal to BAS. Air flow valves and fume hood controls should be from the same manufacturer. Consideration should be given to the sizing the supply air devices such that minimum ventilation requirements set forth by University EH&S is not hindered by the manufacturer minimum capabilities of the device.

Laboratory Exhaust Systems – variable air volume fume hoods shall be installed unless accepted design practice dictates otherwise. Refer to “Standards for the Design, Construction, Maintenance and Use of Laboratory Fume Hoods”, prepared by the Chemical Hazards Use Committee and the Department of Environmental Health and Safety, for additional requirements for fume hood design, construction, use and testing.

University Environmental Health and Safety, along with University Research and Engagement, shall be consulted to design for appropriate occupied and unoccupied air change rates.

www.ehs.umass.edu/fume-hood.html

Supply air delivery must be designed to ensure hood performance and safety. The benefits of a dropped ceiling in achieving optimal air distribution should be considered.

During the design process the University will require an analysis of effluent plume shape and dispersion by a specialist in air wake analysis. Specialist shall be approved by the University. Such analysis is typical for all discharge stacks such as laboratory fume hood or other laboratory discharges.

Exhaust fans handling contaminated air from fume hoods shall discharge vertically from an outlet in compliance with ANSI Z9.5 2012 (or current) which is at least 10 feet above the roof level with a velocity of at least 3,000 feet per minute. Consideration to system redundancy should be given – appropriate University departments should be consulted. For exhaust systems with multiple fans, a fan staging sequence should be implemented to maintain effective discharge velocities


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for each operating fan, in accordance with ANSI Z9.5 2012 or current, without the use of controlled dilution air. If minimum discharge velocity cannot be maintained from each operating fan, designers are encouraged to utilize systems which intake or induce controlled dilution air to maintain minimum discharge velocity. In all cases the exhaust plume must remain clear of other roof lines, air intakes, operable windows, or grade level. Careful consideration to/from the impact of surrounding buildings should be made.

Provisions should be made for local exhaust of instruments, gas cabinets, vented storage cabinets or special operations not requiring the use of a fume hood (local capture devices).

HEPA or charcoal filters are generally not required for most routine uses of fume hoods. Where filters are required, the housing shall be located in the fan room or roof before the blower. The filter housing shall be located to allow for easy filter changing by the bag-in bag-out technique. Exhaust fans shall be sized accordingly to handle the increased pressure drop across the filter.

Each perchloric acid hood shall have an individual exhaust system (i.e., individual duct to individual fan). The ductwork shall go straight from the hood to the roof with no horizontal runs or sharp turns. "Wash-down" facilities shall be built into the hood and ductwork. An air ejector system or an exhaust fan may be used. An air ejector exhaust system eliminates the possibility of acid reaction with fan components and allows for ease of cleaning. If a fan is used, the blades shall be made of acid resistant metal or a metal protected by an inorganic coating. The fan shall be lubricated with a fluorocarbon type grease.

Cleanroom Spaces – air valves controlling each supply and exhaust terminal. Temperature control via recirculation air handling units and make-up air units. Include supplementary air conditioning systems, such as fan coil units, with recirculation air only, for cleanrooms with high sensible cooling loads. Centralized air handling units (recirculation or make-up air types) shall pressurize the plenum outside of the cleanroom space, have chilled water cooling, hot water (glycol) heating with coil (freeze protection) pump, and provide 100% outside air with heat recovery, if possible, from the exhaust air stream. Provide VFDs for supply fans with static pressure control. Where filter fan units are used, they should be capable of variable speed with connection to BAS for speed and filter status. See Section 23 3416 for more information about central exhaust fans and exhaust air controls.

Data Centers – computer room air conditioners (CRACs) with chilled water cooling coils and airside economizer. Provide under-floor supply air ducted to floor tile diffusers. Consider variable air volume controls, such as under-floor boxes or floor tiles with built-in modulating dampers to allow for VFD control of CRAC fans. Include hydronic reheat and steam or atomization style humidification if humidity control is critical to support equipment in the data center. IT equipment will typically be arranged in hot aisle/cold aisle configuration. Design for cold aisle temperatures no less than 60 °F and no greater than 80 °F and hot aisle temperatures no greater than 140 °F, pending compatibility with the specific IT equipment being serviced. Provide cold aisle containment for spaces with anticipated IT loads exceeding 40 W/ft2.

Auditoriums – discuss with UMass project manager the need for a dedicated air handling unit vs. connection to existing air handling systems available. If dedicated air handling unit, provide with chilled water cooling, steam or hot water heating, airside economizer, and variable volume


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supply and return fans with VFDs controlling to maintain space temperature. Include demand control ventilation per code.

Classrooms – for new construction or major renovation projects, either VAV or fan coil systems are acceptable. For fan coil systems, provide one unit per classroom with chilled water cooling and hot water heating coils. Route tempered makeup air from dedicated outside air systems (DOAS) directly to the fan coil units. Provide occupancy sensors. Provide makeup air dampers on the fan coil units to close off makeup air when spaces are unoccupied. DOAS shall have chilled water cooling, steam or hot water heating (HW preferred), fan VFD(s) controlling to maintain static pressure, and heat recovery with the exhaust air stream.

For smaller renovations or where other system types are already used, such as VAV boxes with central mixed-air air handling units, match existing system types elsewhere in the building.

Technology Closets – use of thermostatically-controlled transfer fans with undercut doors for cooling should be considered as a first option design approach. Although specific room loads vary, and mechanical cooling may be needed, general goals of 6 ACHs, 80F room air setpoints are suggested. If mechanical cooling is considered, consider CHW-based cooling (where year-round CHW is available) and employ transfer fan system as a back-up option.

Kitchen/Dining/Food Preparation Areas – kitchen exhaust fans/hoods shall be balanced with related air handling units and make-up air units to provide neutral to slightly positive overall building air pressurization, regardless of varying state of operation for each unit. Require kitchen hood demand control similar to Captive Aire or equivalent with duct static safeties enabled.

CONTROL OF INFECTIOUS AEROSOLS As a University community, UMass Amherst is working to implement institutional, behavioral, and technological responses to the control of infectious aerosols, such as the on-going COVID-19 pandemic. HVAC designers are expected to be familiar with guidance published by the Commonwealth of Massachusetts, the CDC, ASHRAE, and others relevant authorities and should include features and capabilities in design documents that contribute to the University’s mission of improving safety. Designers should meet with the UMass project manager during the OPR and BOD phases and should specifically document changes to the scope of work resulting from these conditions. Designers should also specifically differentiate between intended operation of systems during the pandemic (e.g. increased ventilation, filtration) and after the pandemic.

SECTION 23 0130 HVAC AIR-DISTRIBUTION SYSTEM CLEANING For existing air distribution systems being reused or augmented as part of a project, include a requirement that the contractor clean existing systems prior to installing new additions to those systems.

Designers shall include requirements in the specifications that Contractors protect sections of ductwork during construction prior to installation to avoid accumulation of construction debris and dust. New ductwork must be cleaned just prior to installation as part of all projects.


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SECTION 23 0593 TESTING, ADJUSTING, AND BALANCING GENERAL At the outset of the project, the designer and Owner shall review and discuss the benefit of measuring the existing air or water flows of main trunk ducts or header pipes to quantify the potential impact of the new work on the central system.

Designers shall require that contractors schedule a dedicated TAB coordination meeting with the Owner and Engineer. At this meeting, the TAB contractor shall demonstrate full understanding of their scope of work, confirm schedules, coordinate space and equipment access concerns, coordinate with the ATC contractor regarding required assistance during balancing, and discuss other topics of concern, if applicable.

Contractors shall provide certified test reports in the format specifically approved by the TAB contractor. TAB contractor shall be certified by AABC or NEBB.

Designers should specify what the parameters of airflow, water flow, and temperature will be measured and at what locations measurements should be taken. Be specific in the TAB specifications, for example: "Read supply and exhaust airflows at room diffusers," or "traverse supply and exhaust ductwork in the mechanical room." Specify flow elements, particularly in water systems, to facilitate balancing. In variable flow systems specify the conditions under which they will be balanced.

Final settings shall be clearly and permanently marked on each balancing valve, quadrant, etc. to show final settings.

Direct-drive pumps and fans shall be laser-aligned.

For new HVAC systems or major replacements of existing systems, designers shall specify if sound testing be provided by the Contractor to confirm that maximum noise criteria requirements are not exceeded. If so, contractors shall hire a certified testing firm and shall provide a written report documenting the results of their testing. Sound testing would be expected where noise or velocity concerns are identified during the design phase.

After testing and balancing, close probe holes, restore vapor barrier, and patch insulation with new materials identical to those that were removed.

AIR SYSTEMS The balancing contractor shall be responsible for the labor and materials required for sheave changes necessary for the balanced operation of the system.

Designers shall specify that pressure profiles be measured and recorded for all major air and hydronic equipment, such that the inlet and outlet pressure of each individual component (e.g. coil, damper, valve, strainer) can be reviewed by the designer to confirm systems are operating as designed.

Contractors shall test and derive calibration factors for air terminal devices (such as VAV boxes and fan coil units) at both design minimum and design maximum airflow setpoints.


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For mixed-air air handling units, contractors shall derive the outside air damper positions corresponding to design minimum outside airflow (cfm) at full design supply airflow and minimum supply airflow. These damper positions shall be communicated to the EMS contractor for use in programming, unless airflow stations are being used to control ventilation rates.

As part of the static pressure profile measurements for air handling units, designers shall specify that the contractor check and make adjustments as necessary to confirm that the mixed air plenum pressurization is negative (i.e. not over-pressurized by the return fan).

Contractors shall empirically derive design static pressure setpoints for air systems such that the most hydraulically remote end device receives its design flow. Control of static pressure setpoints for air systems and differential pressure setpoints for hydronic systems shall include automatic reset to minimize energy consumption.

Contractors shall field calibrate all airflow stations and water flow meters. Provide at a minimum two-point calibration, at 50% and 100% design flow, including for VAV boxes. Designer will specify acceptable tolerance.

HYDRONIC SYSTEMS For glycol systems, the Contractor shall provide test results confirming proper glycol concentration prior to initiating any TAB. Refer to Section 23 2500 HVAC Water Treatment for details on glycol chemistry.

Contractors shall empirically derive design differential pressure setpoints for hydronic systems such that the most hydraulically remote end device receives its design flow.

Contractors shall empirically derive minimum chilled water and condenser water pump speeds at which associated chiller(s)’ minimum flow requirement is reached and this information shall be communicated to the Engineer and ATC contractor.

Contractors shall empirically derive minimum condenser water pump speeds at which flow over the cooling tower(s) is achieved and this information shall be communicated to the Engineer and ATC contractor.

SECTION 23 0700 INSULATION DUCTWORK INSULATION Insulate ductwork for the following air streams:

• Supply air • Return/exhaust air upstream of a heat recovery system • Outside air

Do not insulate ductwork for the following air streams:

• Return/exhaust air in systems without heat recovery • Return/exhaust air downstream of a heat recovery system


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Exterior insulation: Fiberglass blanket with minimum density of 2 lbs. per cubic foot and flame-resistant Foil-Scrim-Kraft (or equal) vapor barrier secured with pressure sensitive tape.

Provide continuous aluminum jacketing on exterior ductwork in accessible areas and in areas where ductwork is subject to damage from other sources, such as falling branches. Utilize embossed surface finish to avoid disruptive reflections.

Interior insulation for reduced heat loss: rigid insulation only.

Interior insulation (lining) for sound attenuation only: Rigid fiberglass duct liner board with air stream surface covered with perforated sheet metal, poly vinyl acetate polymer, acrylic polymer, or black composite. Surface covering shall be rated for minimum 4,000 fpm. Coordinate liner thickness with acoustical consultant as required to achieve NC requirements from the OPR. Verify that materials are resistant to fungal and bacterial growth.

Designers shall clearly specify that duct dimensions are to be net free area and devoid of any liner. Designers shall measure a sample of ductwork during construction to confirm the contractor’s conformance with this requirement.

All products shall be made of low VOC materials

Insulation and vapor barriers shall be continuous. Breaks in insulation and vapor barriers such as at brackets, through walls or within dropped ceilings are not permitted. Insulation, vapor barriers, and jackets shall be attached by adhesives and not fasteners so that seals are not punctured.

EQUIPMENT INSULATION Equipment Insulation: Equipment to be insulated to reduce heat losses per manufacturer's recommendations. Provide additional insulation for equipment in occupied spaces.

HYDRONIC PIPING INSULATION Inside Buildings: Molded glass fiber with All-Purpose white jacket and PVC Zeston (or equal) fittings covers. Seal all gaps, fittings and valves associated with said piping.

Outside Buildings: Molded glass fiber with 0.016" aluminum jacket applied over pipe and fitting insulation.

Where insulation is susceptible to damage, either inside or outside buildings, cellular glass insulation such as "FOAMGLAS" shall be used.

STEAM AND CONDENSATE PIPING INSULATION General inside building (to maximum 300oF): Molded glass fiber with All-Purpose white jacket and PVC Zeston (or equal) fittings covers. Seal all gaps, fittings and valves associated with said piping.

General outside building (to maximum 300°F): Molded glass fiber with 0.016" aluminum jacket applied over pipe and fitting insulation.


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REFRIGERANT PIPING INSULATION Cellular glass or closed cell foam plastic with flame-resistant vinyl jacket.

SECTION 23 0800 COMMISSIONING All projects, regardless of size, will be commissioned. The typical commissioning scope of a project will include the following below. Note that scope and effort can be tailored to the magnitude of cost and complexity of the project. However, the intent of the elements below should be captured at a minimum:

• Design documents peer review • Commissioning specifications • Commissioning plan development and management • Contractor submittal peer review • Observation and/or coordination of TAB • Pre-functional testing • Functional performance testing • Initial acceptance BAS trend review • Seasonal BAS trend review(s) • Development and management of the commissioning issues log • Closeout documentation review • Coordinate and lead Owner staff training

Projects with an anticipated MEP construction cost of over $1M will utilize a third-party commissioning agent. For these projects, the commissioning agent will provide commissioning specifications. The designer shall review and incorporate these specifications into the bid documents.

Projects that do not feature a third-party commissioning agent will be commissioned by the designer or internal UMass staff. Coordinate with the UMass Project Manager. The designer shall provide commissioning specifications as part of the bid documents and shall develop these specifications in consultation with the relevant UMass stakeholders.

SECTION 23 0900 CONTROLS BACKGROUND The University of Massachusetts at Amherst utilizes a Johnson Controls Metasys Building Automation System (BAS) as its operating platform for HVAC operations, energy management, electrical and steam demand control, and it distributes alarms via email and text message. It incorporates a virtual server (ADX-01) which provides secure web access, serves up graphical user interface, stores long term trend data on all systems, and archives control system programming. This system integrates both legacy Johnson Controls equipment (N1 devices including approximately 50 Network Controllers (NC’s), and current generation Network Automation Engines into a unified operating platform.


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This BAS is connected to all significant campus buildings and is used to monitor, operate, and maintain HVAC and lighting control systems. It is critical to proactive service response for the safety of building occupants and equipment. All control systems must be connected and accessed through the Metasys user interface. Connections should include down to the room level, where reasonably feasible, and there is a Metasys presence in the building. Existing system architecture as described below will be maintained. Review BAS connectivity approach with the Physical Plant Controls Engineer during design. Automatic temperature control systems shall be DDC type connected directly to the campus BAS at the building level. Utilize BAS controls for rudimentary lighting control and monitoring as well, such as basic scheduling.

Use current generation BAS hardware and upgrade existing BAS infrastructure to accommodate this wherever feasible. Software and point definition shall match existing systems, allowing for effective point recognition and queries (see paragraph below) DDC systems shall be fully compatible with existing campus BAS, sharing all data and commands in real time with all existing controllers, workstations and user interfaces. User interface will be through Johnson Controls User Interface (UI), web-based user interface.

The BAS shall monitor and control occupied, partial occupancy and unoccupied operation of HVAC systems to reduce or shut-off ventilation air, exhaust air, fan systems, pumps, etc. The BAS shall control local room day/night temperatures and shall monitor local space temperatures, humidities, occupancy, and occupant adjusted set points. Where possible, radiation should be used as the first stage of heating or cooling during unoccupied periods before cycling on ventilation systems.

SYSTEM ARCHITECTURE To maintain the effectiveness of the BAS in campus building operations, maintainability and data collection, all new components must be similar and integrate seamlessly into the existing architecture as described below.

The ADX-01 virtual server as the primary user interface, providing web-based access, password administration matching campus requirements. It provides graphical interface for all systems showing system layout, operating points and setpoints, as well as customizable user views. All new projects will utilize Metasys User Interface (UI) graphics. The ADX provides long term storage of trend data on all system points for an indefinite time period and customizable trend studies and custom summaries. The ADX records and sorts an audit file of all operator transactions. It transmits alarm information according to user groups, systems, and alarm priorities via email and text. The ADX supports third party access to system data for performance monitoring. Standalone supervisory controllers (Network Engines) in buildings on and off the UMass campus maintain communication to the ADX.

Network Engines in each building maintain communication with field equipment controllers (CGM’s/CVM’s) via BACNET/MSTP communication buses. The Network Engine provides local web-based user login similar to the ADX with similar password protection and viewing capabilities. It stores short term trend data for periodic upload to the ADX. It has time clocking and all system schedules for systems in its building. It provides global sharing logic between all connected field controllers on its MSTP trunks, as well as sharing point data with other system


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Network Engines. It provides BACNET IP integration to third party specialty system. The Network Engine maintains these critical BAS functions even in the absence of communication to the ADX server.

Field equipment controllers read point data and execute control sequences at the local level. All field devices are wired to them. They provide fully customizable control logic for all connected points. These controllers support a secondary sensor and actuator bus which communicates to multifunction end devices, (combining room temperature/humidity/CO2/and occupancy for example) providing intelligence to them and minimizing need for home run wiring.

For additional standard specifications on relevant controls hardware, refer to the attached Appendix 1 titled UMass Amherst BAS Hardware Specifications 2020.pdf.

Review any utility metering needs with UMass Physical Plant Controls engineer. Provide metering equipment to all major utilities serving the building, (steam, water, chilled water, electricity) if not already established, reporting to the campus BAS. Building electric meters will be part of the campus’ PowerLogic system and will also be read by the BAS. Any need for submetering should be reviewed with UMass.

To assist efficient operation and maintenance, provide equipment status and alarm monitoring system pressures, air filter differential pressure, air and water flow for large systems, VFD and fume hood monitor network connection. Match existing campus sequences wherever possible.

Adequate points will be specified so that system performance can be controlled and verified and performance and maintenance alarms reported. (Typical systems along with hardware and software objects are listed below.)

Provide individual zone controls to occupants wherever practical.

NEW CONSTRUCTION AND RENOVATION WORK New construction and renovation will incorporate BAS based controls on all HVAC equipment, from central systems down to terminal or packaged terminal units. (i.e. new air handling units). As applicable, this will include monitoring of steam flow, steam condensate flow, chilled water flow, domestic water use, and overall facility electrical use. Minor renovations will do the same when the building has an existing BAS. Adequate points will be specified so that system performance can be controlled, verified, and has the ability for performance & maintenance alarms to be reported. (Typical systems along with hardware and software objects are listed below.)

Minor renovations (for example room renovations or equipment replacement or addition) will do the same when the building has existing BAS presence.

All new systems and objects will be integrated into the existing BAS operating platform for operator access, trending, and alarming. All new BAS objects will be accessible to existing controllers, and new controllers will be able to access all existing BAS objects.

Include the demolition of any existing controls equipment, electrical or pneumatic, that will no longer be used. Include all abandoned, obsolete equipment and associated wiring, even if it goes beyond the affected project area.


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Review any demolished or salvaged control equipment with the University for possible retention prior to disposal.

CONTROLS INSTRUMENTATION MOTORS Specify analog current sensors. Derive status from current measurements using an adjustable threshold value. Do not specify current or pressure switches to determine status.

Hard-wired analog outputs (e.g. 0 – 10 VDC or 4 – 20 mA) from VFDs for amperage or power are acceptable in lieu of a separate current sensor. Amperage or power points communicated over BACnet or other communication protocols are not acceptable.

THERMOSTATS Specify thermostats with digital display and adjustable control for occupants. Limit the range of adjustment through software, rather than through the thermostat itself.

OCCUPANCY Occupancy sensors are preferred for spaces with consistent numbers of occupants (e.g. offices, classrooms, conference rooms). CO2 sensors are preferred for larger spaces with more variable occupancy levels (e.g. conference rooms, auditoriums). People counters are not preferred. Specify an occupancy sensor or CO2 sensor for all occupied spaces unless otherwise directed by the UMass project manager.

Occupancy sensors shall use passive infrared technology. Specify sensors with auxiliary output contacts so that the same sensor can be used for HVAC and lighting circuits. Do not specify wireless occupancy sensors unless ceilings or walls are inaccessible to run wires. Do not set time delays via dip switches or other inputs on the sensor itself. Program time delays as adjustable analog variables within the BAS. Designers shall check the visibility range of proposed sensors and create rough layout plans to confirm whether multiple sensors are required to cover the entirety of a room. Specify that multiple occupancy sensors in the same room shall be wired such that if any sensor is active, the room is considered occupied and only if both sensors are inactive is the room considered unoccupied.

HYDRONIC SYSTEM WATER FLOW Specify at least one water flow meter for each primary and each secondary hydronic loop. Where pipe routing does not allow sufficient straight run for an accurate measurement, specify multiple meters in the various branches of the system to calculate total flow.

In line electro Mag meters are preferred similar to Onicon FT03000 series equal or better. Ultrasonic meters may be used only if straight pipe requirements of the manufacturer are achievable. Where insertion meters are required Electromagnetic are preferred. equal to F3500 series or equal.

Meters with digital displays are preferred.

Designers shall locate meters on drawings indicating preferred locations.

Select meters to maintain accuracy at turndowns of at least 5:1.


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AIR FLOW Specify airflow measuring stations for outside air, return air, and supply air of all air handling systems over 10,000 cfm. Specify airflow measuring stations for primary air on all applicable terminal devices.

Pitot tubes or differential pressure type are preferred for applications with turndowns up to 5:1. Thermal dispersion probes are not preferred.


Refer to laboratory systems for specialized air flow measurement.

STEAM FLOW Provide steam metering at each building, reporting to the Campus energy management system. If multiple steam lines serve a single building or if no accessible location is available for the single steam main, meter individual branches and calculate total flow.

Meters should be sized to handle the expected maximum and minimum flows.

Orifice plate flow element are preferred.

Meters should be Multi variable type with built-in temperature and pressure compensation in calculating flow rates. Equal to Rosemount 1151 with hart output for pressure and temperature with local or remote display.

All piping shall be stainless steel with recommended pitch and tees for calibration purposes.

CONDENSATE FLOW Provide condensate metering at each building, reporting to the Campus energy management system. If multiple condensate lines serve a single building or if no accessible location is available for the single condensate main, meter individual branches and calculate total flow.

Meters should be sized to handle the expected maximum and minimum flows. Meters shall distinguish bidirectional flow and the BAS shall alarm upon sensing reverse flow.

Ultrasonic meters are preferred. Design piping to meet straight pipe requirements of the manufacturer.

Specify that a temperature sensor be installed in the condensate pipe upstream of the meter so that mass flow can be calculated from the measured volumetric flow.


DOMESTIC WATER FLOW Ultrasonic meters or Inline Electro Mag Meters are preferred. Integrate water meters into the campus BAS. Provide both analog and pulsed totalization output to show both rate and unit total.

WATER DIFFERENTIAL PRESSURE Differential pressure sensors shall be specified for all secondary and all variable primary hydronic loops. Locate these sensors at the most hydraulically remote coil per ASHRAE 90.1. Note this location on plan drawings and confirm it is accessible for future service. Differential pressure


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sensors may be used to control bypass valves. Do not use differential pressure sensors to control flow through chillers or heat exchangers.

Provide a differential pressure sensor and manifold valve assembly with bypass to be piped with external isolation valves and reference gauges.

Black iron piping not acceptable.Sensors with digital displays are preferred.

AIR STATIC PRESSURE Air static pressure sensors shall be specified for all variable volume air systems. Locate sensors approximately 2/3rd of the distance between the fan and the most remote terminal device. Note this location on the plan drawings and confirm it is accessible for future service.

WATER TEMPERATURE Water temperature sensors shall be specified for the supply and return flows of each hydronic loop, as well as the inlet and outlet temperature of all primary equipment, such as chillers, boilers, and heat exchangers.

Temperature sensing by nickel-based RTDs (resistance temperature detectors) are preferred.

AIR TEMPERATURE Air temperature sensors shall be specified for the return air, mixed air, and supply air streams of each air handling systems. Specify air temperature sensors directly after each heating or cooling element (e.g. coil, burner).

Confirm that each building has at least one reliable outside air temperature sensor. Locate outside air temperature sensors in shaded areas or in radiation-protective enclosures.

Specify air temperature sensors in the discharge air stream of each terminal device with a heating or cooling element and an additional sensor in between the heating and cooling element if both are present.

DAMPER POSITION FEEDBACK Provide end switches on isolation dampers serving critical spaces.

VALVE POSITION FEEDBACK Specify valve actuators with position feedback for modulating chiller flow control valves and hydronic coils with valves over 4 in.

CONTROLLER AND POINT NAMING CONVENTIONS Wherever possible, follow existing format already established within the building where new controls are being considered. This is intended to facilitate queries and other data extraction procedures across multiple installations.

Field controllers should be named to facilitate their location, operations, and maintenance. They should bear the name of the system they are controlling, or the rooms they control. For example, a controller which controls the air handler “AHU1A” should be named accordingly. A controller which does temperature control in three rooms should bear the name of the rooms, for example, “E463-463” if it controls those rooms.


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Point naming conventions: A key objective in point naming is for the object name to describe the building, system or room, and function of the object. three part, describing the building, system, and end point in a unified manner that is searchable. In the name “MAHAR.AHU1.PH-VLV” for example, five letters are used for the building name, the system is easily defined, and the analog output is going to a valve controlling a heating source. The following are examples:

Name Type Description Trending

MAHAR.HXT.EF2-C BO Control output for EF2 associated with system HXT

Change of State

MAHAR.HXT.EF2-S BI Status input for EF2 run status

Change of State

Other abbreviations: -VLV valve, OA -DPR outside air damper, -T temperature, -H humidity,

Review proposed point name with the Physical Plant control engineer

TREND LOGS Specify that the contractor configure BAS trend logs for all analog inputs, analog outputs, digital inputs, digital outputs, BAS setpoints, third party BACnet points integrated into the BAS, and all other BAS system variables used in their associated sequences of operation (e.g. occupancy mode).

Enable trends for extended logging such that trends are archived and available for review for the duration of the warranty period and remain in effect indefinitely for use in Operations. Implement 15-minute (or shorter) time intervals for analog points. Change of state trending may be used for binary points. Setup trend groups such that all relevant points are automatically viewed and downloadable together.

INTEGRATION OF THIRD PARTY (NON-BAS) SYSTEMS AND EQUIPMENT Use of factory packaged control systems on HVAC equipment will generally be provided for but limited to chillers, variable flow refrigerant system controllers, electrical submetering, and other equipment or systems where direct BAS control or monitoring is not practical. This shall only be completed with prior approval by both Design & Construction Management (DCM) and Physical Plant (PP) engineering staff.

Full DDC control of air handling units is strongly preferred as opposed to packaged controllers from the AHU original equipment manufacturer (OEM). Packaged OEM controllers may be used for smaller applications with approval from the UMass Project Manager. When integrating packaged OEM controllers with the BAS, specify that the BAS shall have hard-wired control signals (e.g. 24 VAC, 0 – 10 VDC) to the OEM controller for the following critical points so that the AHU can continue to operate if network communication is lost.

• Occupied mode • Space temperature setpoint, if adjustable through a BAS thermostat or graphics


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• Space temperature feedback, if from a BAS thermostat or calculated as the average of multiple zones

• Discharge temperature setpoint, if adjustable through the BAS graphics The designer is responsible for reviewing the OEM controller documentation and tailoring the points list and sequence of operation to the available points and functions built into the controller. Do not utilize boilerplate sequences of operation that may not be achievable by the specified controller.

All OEM controllers shall be certified BACnet devices. Do not use other communication protocols. The designer is responsible for providing the ATC contractor with a specific list of BACnet points to be communicated to the BAS and displayed on the graphics.

All VFDs shall be configured to receive a direct analog speed signal (0 – 10 VDC, 4 – 20 mA, etc.) from the BAS, as well as a digital output for start/stop, provide a digital input for status and alarm. A BACnet/MSTP integration connection will be provided to read drive diagnostics and motor kW.

All third-party lighting control systems will be integrated into the BAS and will allow monitoring of all inputs and outputs and allow scheduling to be performed through the BAS. Refer to electrical guide specifications for allowable manufacturers.

Integration should be accomplished with a local Master/Slave/Token Pass (MSTP) trunk whenever possible, rather than using a campus Ethernet drop for BACNET/IP. Integration points will be mapped into the BAS with point names describing their function.

TECHNIQUES FOR INSTALLATION AND WIRING Wiring will generally adhere to the National and State Electrical Codes.

Wiring exposed in mechanical spaces will be in EMT conduit, minimum. Rigid conduit may be required in special conditions – refer to Division 26 specifications for specifics. Low voltage control wiring shall not share conduit with higher voltage power wiring. MS/TP trunk shall be routed within conduit. Open cables are acceptable above plenum-rated ceiling spaces and shall be plenum-rated. Control cabling shall not be run within cable trays or raceways used for other communications.

Cables will be uniform across an installation/project. White jacketing is preferred.

Non-labeled control automation junction boxes and above-ceiling control panels shall be blue color.

All cables will be print-labeled at their terminations, with indelible marking, both on the jacket and with Brady-style markers or wrap-around tags, according to their BAS point name (i.e. power wiring, breaker location, control transformers, UPS’s, etc.)

All end control devices, with the exception of zone sensors, shall have a printed system name and field point/object name label.


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DOCUMENTATION, CONTROL DRAWINGS, AND GRAPHICS SUBMITTALS Designers shall specify that contractors adhere to the following submittal requirements:

• Include a plain English narrative of the controls system architecture and sequence of operation intent

• Include written sequences of operation tailored to the specific requirements of the design and the limitations of the proposed hardware. Contractors shall not be permitted to duplicate design sequences of operation in the submittal. Contractors shall provide recommended values for parameters such as deadbands and time delays.

• Include wiring diagrams • Proposed locations for sensors • Include controls schematic drawings • Include product data for all new devices. Contractors shall be responsible for marking up

manufacturer’s product data to call out specific models, options, sizes, etc. applicable to the project.

• Include mockups of graphics. Graphics may be live on the system, rather than printed to PDF, if desired.

Contractors shall make program code available to the designer to review and approve prior to commissioning.

EQUIPMENT/SYSTEM GRAPHICS Use a background image customized to match the actual configuration of the piece of equipment. Show sensors in their approximate locations. Show the value of a measured variable next to its sensor on the graphic, rather than in a list or summary table.

Indicate on the graphic the area served and any upstream systems that the serve this particular piece of equipment (e.g. for a VAV graphic, indicate which AHU it is served by).

Users with sufficient privileges shall have the ability to start or stop equipment through the graphics and to change the lead, lag, backup, etc. designation of each piece of equipment that is staged in series.

Show set-point values next to the control point feedback. Do not make tuning parameters of control loops adjustable through the graphics.

Indicate active alarms with a change in text color and/or a separate icon.

Flow arrows shall be used for all air AND water flows.

BACnet points shall be differentiated visually on the graphic.

All equipment overrides shall be designated in red text and alarmed after 24 hours.

Include a link on the graphic to a PDF or similar format of the sequence of operation and as-built control drawings.

Include a link on the graphic to the associated floorplan graphic, if applicable.


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For terminal device graphics, include a link to the primary system graphic.

FLOORPLAN GRAPHICS In general, graphics will utilize actual detailed floor plans, showing current room numbers. Renovation work will update existing floor plan graphics or create new.

Include a link to relevant control drawings on the graphic.

Thermostat locations shall be shown on the floor plan graphic in their approximate as-built location. Include a line clarifying which thermostat is associated with which device.

Show the location of other system sensors, such as static pressure sensors, differential pressure sensors, or building pressure sensors, on floorplan graphics.

SUMMARY GRAPHICS Provide summary graphics for all similar types of equipment with their key inputs and outputs. For example, include a lab summary page for each floor with each lab’s space temperature, total supply flow, total exhaust flow, air change rate, and airflow offset.

RECORD DRAWINGS Final as-built control drawings shall be submitted after training and reviewed by the Physical Plant engineering team. All the comments and modifications captured during the review process shall be reflected in the final closeout package.

Any change in equipment sequence of operation, whether it is a renovation or small upgrade, shall be updated on the as-built documents.

TRAINING The designer shall include requirements in the specifications for the Contractor to provide Owner training. Provide field walk through and classroom training. Provide advance syllabus and preliminary control drawings prior to training. Include commissioning agent.

PNEUMATIC CONTROLS Typically, new designs will not incorporate new pneumatic control air systems. However, there may be cases where new renovations will connect to existing pneumatic control air systems.

Control air compressors shall be alternating duplex-type with refrigerant air dryer. Tank mounted (ASME stamped tank) duplex compressors sized to meet peak system demand shall be used. Compressor shall be belt driven, oil lubricated with air intake filter.

Copper pipe, type K or L, shall be used where air-line is exposed. Fire rated virgin black polyethylene tubing (Dekoron or equal), 2000 psig tensile strength, with vermin resistant treatment, with barbed brass fittings may be used if run through conduit.

For long pipe runs, control air shall be delivered at full line pressure with a pressure reducing valve mounted near the final point of delivery or equipment at a pressure of 25 psig.

Existing pneumatic lines that are being demolished or terminated shall be removed back to the closest active branch or as far back as practical. All terminations shall be completed with UMA-


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approved caps and seals. In addition, any unused or abandoned control devices shall also be removed.

For copper piping, use a threaded or compression fitting

For polyethylene piping, use a barbed or compression fitting

SEQUENCES OF OPERATION In general, adhere to latest ASHRAE Energy Conservation Standard 90.1 and ASHRAE Guideline 36 for High Performance Sequences of Operation. The current version of 90.1 describes a number of control strategies for HVAC and lighting systems.

Take advantage of no or low occupancy to shut off or reduce HVAC energy input. Include occupancy sensors tied to HVAC whenever possible. Incorporate reset strategies for part load conditions whenever possible.

The designer will write sequences of operation for all equipment controlled by the HVAC control system. Please strive for simplicity while providing accurate control of temperature and ventilation with minimum energy consumption.

The designer shall provide a plain English controls narrative at the beginning of the sequence of operation explaining the general intent of the system.

The sequence of operation shall specify the actions of each system component starting from the unit being off, proceeding to startup, and then transition to normal operation. The same shall be provided for shutdown. At each stage, the design shall specify what conditions must be met to proceed to the next step (e.g. upon confirmation that the damper is open via the end switch).

The designer shall specifically designate which device is controlling which functions in systems with multiple controllers or pieces of equipment. For example, in a chilled water system, the design shall specify which functions are accomplished by the chiller’s OEM controller as opposed to the BAS controller.

The designer shall specify initial values of all setpoints and setpoint ranges, but shall designate which values shall be empirically derived in the field by the contractor and/or commissioning agent. For example, all static pressure setpoints shall be empirically derived by the TAB contractor to be the lowest possible static pressure that still allows the most remote box to achieve its design airflow with its damper 100% open.

The following energy management routines shall be employed wherever possible:

• Time of day scheduling with exception schedules allowing for changes on holidays or while a unit is being serviced

• Start/stop time optimization • Comparative enthalpy economizer control– in general, the University prefers

comparative enthalpy economizer controls, but comparative dry bulb economizer sequences with or without an outside air enthalpy high limit are acceptable on a case by case basis with approval from the UMass Project Manager.

• Supply air static pressure reset


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• Supply air temperature reset– note that University prefers that static pressure reset be prioritized in the sequence of operation such that the supply temperature setpoint does not reset until the static pressure setpoint is at its minimum.

• Demand control ventilation (DCV) – note that the University prefers that DCV be implemented using space CO2 sensors, rather than return air CO2 sensors. All spaces shall utilize a CO2 setpoint per ASHRAE 62.1 and the AHU shall have a different CO2 setpoint that is slightly higher than the highest space CO2 setpoint. If a space’s CO2 rises above its setpoint, the terminal device shall increase its primary airflow in response. If the highest of all the space CO2 sensors rises above the AHU’s CO2 setpoint, the BAS shall increase the AHU’s minimum airflow setpoint. The AHU minimum airflow setpoint shall be limited not to fall below the minimum outside air flow required by ASHRAE 62.1 for zero occupants in the design square footage and not to rise above the design minimum outside airflow.

• Chilled and hot water differential pressure reset • Chilled and hot water temperature reset– note that University prefers that differential

pressure reset be prioritized in the sequence of operation such that the supply temperature setpoint does not reset until the differential pressure setpoint is at its minimum.

• Condenser water temperature reset – in general, the University prefers that condenser water temperature setpoints be reset based on the outside air wet bulb temperature to maintain a constant cooling tower approach (e.g. 7.5 °F).

• Variable primary water flow control – for primary/secondary loop configurations, designers shall specify variable primary loop control when primary pumps are greater than 10 hp. In variable primary scenarios, the primary pumps shall be controlled to maintain a primary loop flow equal to 110% of the measured secondary loop flow.

• Variable condenser water flow control – condenser water pump VFDs shall modulate to maintain the minimum condenser water loop differential temperature that the chiller can safely support (e.g. 5 °F).

All control functions shall be executed within the control unit. University personnel shall be able to customize control strategies and sequences of control and shall be able to define appropriate control loop algorithms and choose the optimum loop parameters for loop control. Control loops shall support any of the following control modes:

• Two position • Proportional • Proportional plus integral • Proportional plus integral plus derivative

The University prefers that reset strategies be based on feedback from the downstream devices (e.g. polling of VAV damper positions) rather than global inputs such as outside air temperature or time of day.

The designer shall include low level fault detection alarms, including the following:

• Valve commanded closed with a temperature differential across the coil


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• Valve commanded open with no temperature differential across the coil • Airflow measured with damper commanded closed • No airflow measured with damper commanded fully open • Heating and cooling systems active at the same time

LAB VENTILATION CONTROLS All below sequence sections are as applicable to the equipment specific to the lab zone(s) being designed. The overarching control of lab zones is such that each lab zone should control to an occupied and unoccupied air change rate as dictated by occupancy sensor with supply airflow devices tracking the total measured exhaust airflow (all hoods, general exhausts, specialty exhausts) from the lab zone to maintain pressurization.

The University strongly prefers BAS control of lab zones as compared to control by third-party controllers integrated into the BAS via BACnet for monitoring. The use of third-party equipment controllers, for example for air valve flow control, is permitted; however, control of zone-level functions, such as occupancy, temperature control, general exhaust control to maintain air change rate targets, and supply airflow control to maintain airflow offset targets, shall be accomplished by the BAS zone controller.

EXHAUST AIR • All lab ones shall maintain an occupied and unoccupied total exhaust flow setpoint which

correlates to the occupied and unoccupied Air Change Rates set forth by the University. • The exhaust total flow setpoint will change with space occupancy between the occupied

and unoccupied total exhaust flow setpoint. This setpoint includes all exhaust flows measured within the space and will be used to calculate the general exhaust flow setpoint. Occupancy shall be controlled by zone occupancy sensors and should not be schedule based.

• The general exhaust (GEX), if applicable, will modulate to maintain its calculated airflow setpoint based on the following:

o The total lab specialty exhaust flow (fume hoods, snorkels, canopies, etc.) shall be monitored and used to calculate the GEX airflow setpoint based on the space exhaust total flow setpoint. The calculation is as follows:

§ GEX-CALCFLOW-SP = EXH-TOTALFLOW-SP – Sum of specialty exhaust o The resulting general exhaust setpoint shall be proportionally split between

multiple general exhaust devices (if applicable) based on device size. • Calculated lab ACH and occupancy based ACH setpoint shall be displayed on the Building

Automation System for monitoring by the University.

SUPPLY AIR • The supply valve(s) will modulate to track the measured total exhaust airflow (GEX, Fume

Hoods, Specialty Exhausts) plus a fixed differential setpoint. The differential may be positive or negative depending on the lab’s relationship to adjacent spaces as set forth by the University.

• The resulting supply flow setpoint shall be proportionally split between multiple supply devices (if applicable) based on device size.


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• Calculated lab airflow offset (positive or negative) and associated airflow offset setpoint shall be displayed on the Building Automation System for monitoring by the University.

EMERGENCY PURGE • Emergency Purge: Emergency purge should be controlled such that lab ventilation

increases to a maximum Air Change Rate set forth by the University with consideration given to device quantity and capacity such that under purge operation, the exhaust air devices within a zone do not out flow the supply devices and lab pressurization can be maintained/

ALARMS • Alarms shall be generated to indicate if there are failed airflow devices by comparing

measured flow with flow setpoint, taking into consideration the position of the airflow device damper.

SECTION 23 2100 PIPING GENERAL Water lines of any sort shall not be installed over electrical switchgear, motor control centers, transformers, electrical panels, nor in elevator machine rooms and shafts.

Follow manufacturer’s recommendations for proper installation of valves, fittings, transitions, and any appurtenances for any specific piping systems employed.

Good piping practices will include:

• Minimizing number of fittings wherever possible • Long radius elbows used wherever possible • Valve installations with adequate straight pipe lengths before and after the valve. • Adhere to best industry standards to minimize pressure drop design. • Follow ASHRAE 90.1 requirements to size pipes for minimum life cycle cost based on

anticipated annual run hours of the system.

Process (continuous) loads and HVAC equipment loads shall be separated onto different loops. Where flow and pressure requirements of the process loads loop significantly differ from the flow and pressure requirements of the HVAC loads loop, consider the installation of a heat exchanger between them.

Use non-conducting dielectric connections whenever joining pipes of dissimilar metals.

Use flanges, unions, or grooved couplings to allow disconnection of equipment or components for servicing; do not use direct welded, soldered, or threaded connections.

Designers shall specify that Contractors take care to protect piping materials stored on site and during construction to avoid accumulating construction debris. All systems shall be cleaned with a commercial grade cleaner, circulated and flushed under the supervision of a water treatment contractor. Coordinate with the UMass water treatment specialist prior to start of water treatment installation work.


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Hydrostatic testing of all piping shall be completed to 125 psig or 1.5 times its rated working pressure, whichever is higher, for a period of at least 4 hours. Provide documented record of testing and sign-off from the on-site construction project manager or similar UMass representative with overall responsibility of the project.

PIPING SYSTEMS The University does not have specific requirements for piping materials, construction, and fitting types for hydronic systems. Designers are expected to be familiar with current industry practices, including the relative cost and performance of various materials and fittings, and designers should make recommendations to the University that are consistent with the OPR and the project budget.

Chilled water and condenser water supply and return piping shall be copper for pipe sizes up to two inches. Use of black steel in these sizes is discouraged.

Grooved mechanical joints (i.e. Victaulic or equivalent) may be used in accessible indoor locations only if approved by the UMass Project Manager. If grooved joints are used in systems with glycol, designers shall specify that the Contractor thoroughly clean and flush the piping systems prior to filling to confirm that no adhesives, detergents, or other chemicals from the pipe installation process are left to contaminate the glycol solution.

STEAM AND CONDENSATE HEATING PIPING Steam is generated at the University Power Plant and is distributed throughout the campus through a piping distribution system. Generally, the steam leaves the power plant at 15-18 psig and 75-95 psig at 245 °F – 450 °F. Condensate is returned to the power plant using gravity and pumped condensate return piping systems at temperatures ranging from 125 °F – 180 °F.

Trenches or tunnels are preferred for steam distribution systems. Where direct buried piping must be used, with prior approval from the UMass project manager, it will be drainage/dryable systems equal to Perma-Pipe Multitherm 500.

The designer shall be aware of the danger of injury or death that might occur due to condensate induced water hammer (CIWH). Steam traps should be provided for the removal of condensate at collection points in steam piping systems and at drip legs, unit heaters and at terminal ends of companion piping. All low points in steam lines and the ends of long headers should be provided with drip legs and traps. Test stations at the outlet side of steam traps should be installed. On headers with long sections at one elevation, drip legs should be installed at intermediate points in addition to those at low points and at the ends. Steam traps should be installed below and close to the equipment or pipeline being drained and the trap should be accessible for periodic inspection. Each trap should serve only one collection point and shall be properly sized for both flow rate and ANSI pressure rating. Steam trap discharge lines shall be sloped for drainage where possible. Do not design vertical condensate risers at the discharge of steam traps. Where possible, condensate return lines should be routed back to the main risers at the same elevation or lower compared to the trap discharge. The designer shall apply the trap manufacturer's recommended safety factor when sizing traps but in no case shall a safety factor less than 3 be


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used. Strainers with blow down valves shall be located ahead of each float and thermostatic (F&T) trap.

For coils with modulating steam control valves, follow the specific coil manufacturer’s installation guide. In general, provide a vacuum breaker with a check valve and an air vent on the discharge line from the coil before the trap. Include a minimum 14” height difference between the vacuum breaker and the trap inlet. Confirm the trap has sufficient drainage capacity at 0.5 psi of pressure differential resulting from the 14” height difference.

Steam lines shall be engineered with provisions for expansion and the removal of condensate. Generally, bends or loops shall be used to absorb the pipe expansion and contraction. Expansion joints or ball joints may be used in manholes.

Pipe anchors to control movement of piping shall be shown on the design drawings. Anchors shall be welded to the pipe, but the anchor connection to the building structure must be bolted. Provide structural support for all kinetic forces.

Pressure reducing valve (PRV) shall be located to be accessible without the use of a ladder. All gauges shall be readable from the floor. Pressure gauges shall be selected to read the normal system operating pressure at the midpoint of the gauge. Each regulator shall be valved so as to allow its removal from the system while the system is in operation.

Valves 4 inches and above shall have by-pass systems.

HYDRONIC SPECIALTIES Follow manufacturer’s recommendations for proper installation of valves, fittings, transitions, and any appurtenances for any specific piping systems employed.

Provide high quality air removal devices. Spirovents or equivalent are preferred.

Specify that automatic air vents with separate manual valves as backup shall be installed at the highest point in each hydronic loop.

Provide balancing devices capable of reading and adjusting flow at the terminal unit. Bell & Gossett Circuit Setter or equivalent. On CHW systems, use automatic flow-regulating devices at the terminal unit above 2 gpm, 2 psi drop min.

Utilize sand filters for condenser water systems with open cooling towers. If sand filters cannot be provided, then at minimum provide a loop connection point for a portable/rented sand filter to be attached.

Specify flexible connections to equipment located on outdoor structural pads to allow for general vibration isolation and pad settlement over time.

STEAM AND CONDENSATE HEATING SPECIALTIES Each steam service entrance shall have a low point with a full-size dirt leg at least 8" deep, located ahead of the first valve. This dirt leg shall have a 2" nipple and cap in the bottom to facilitate cleaning. Trap take-offs shall be at least 2" above the bottom. Each leg shall have two take-offs, each equipped with steel body root valves, with 2" of

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DIVISION 23 HEATING, VENTILATING AIR CONDITIONING (HVAC) HVAC... · 2020. 11. 16. · DIVISION 23 – HEATING, VENTILATING & AIR CONDITIONING (HVAC) ... The purpose of these design