31B-311 HVAC Performance Spec 02-02-09PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 1
SECTION 15600- HVAC
PART 1 – GENERAL
1.01 RELATED DOCUMENTS
A. All of the Contract documents, including General and Supplementary Conditions and
Division 1, General Requirements, are hereby made a part of the work of this Section 1,
the more stringent requirements shall govern.
B. All work shall comply with all federal, state, and local codes and any other authorities
having jurisdiction.
1.02 SUMMARY
A. Perform work and provide materials and equipment as required for a complete and
operational HVAC system as shown on the Drawings and as specified in this Section.
Completely coordinate with work of other trades and provide for complete and fully
functional installation. When the word “provide” is used in this specification, it shall mean to
furnish and install. The HVAC contractor shall provide a complete set of design plans
stamped by a registered professional engineer.
B. The work shall include, but is not limited to, the following major items of work:
1. Complete HVAC system for the building. Design and installation shall be in accordance
with the Massachusetts State Building Code. Systems shall be capable of maintaining
spaces at 72 deg. F. in the winter, and 75 deg. F. in the summer. Ventilation
requirements shall conform to the more stringent density and ventilation requirements of
either BOCA Mechanical Code 1993 or ASHRAE 62-1989 Standard for Ventilation
which dictates 20 cfm per person of outdoor air for assembly space, but in no case shall
overall assembly densities be calculated at less than 1 person per 30 SF. Refer to Code
and Standard for additional classifications and requirements.
2. Design drawings stamped by a registered professional engineer in the State of
Massachusetts.
3. Complete HVAC duct system including diffusers, registers, grilles, dampers, etc…
4. Miscellaneous steel, dunnage, supports, hangers, pads, etc., as shown, and as required.
5. Basement
a. New two pipe fan coils to serve the classroom spaces.
b. (New air-to-air heat recovery ventilation to provide ventilation to the new classroom.
New unit to be complete with a hot water heating coil and chilled water cooling coil.
c. New ceiling exhaust fans to serve the two new bathrooms.
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 2
d. Provide a separate price to replace the existing boilers with two gas fired
condensing boilers equal to Viessmann.
e. Test all existing controls and replace any worn.
6. First Floor
a. Remove the existing unit ventilators in Office 113 and cap louver and all piping.
b. Install new two pipe fan coil units in Office 113, 112, and Hallway 114.
c. Provide ducted ventilation air from the new air-to-air heat recovery unit to Office
Spaces 113, 112, 116, and Hallway 114.
d. Test all existing unit ventilators and fan coil controls and replace all failed
controls.
e. Provide exhaust fan at childcare area toilet room.
7. Second Floor
a. Install a new unit ventilator in Classroom 212 to serve the space if the folding
partition is closed.
b. Replace all existing fan coil and unit vent controls.
c. Relocate the existing fan coil unit in the elevator lobby.
d. Provide new exhaust fans in the renovated bathroom.
e. Install new fan coil unit in the new breakroom and extend new exhaust air to the
spaces.
8. Provide all new and renovate all existing piping and all related accessories.
9. Insulation, thermal and/or acoustic, for ductwork and piping.
10. Automatic temperature controls (Base bid – replace all non-functioning controls;
Alternate bid – Replace all controls with new ddc controls).
11. Instruction manuals and startup instructions.
12. Equipment bases and supports.
13. All rigging and hoisting of equipment as required.
14. Access doors on sheet metal ductwork, sheet metal panels and enclosures.
15. Pre-fabricated or field erected curbs.
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 3
C. Related Work Specified Under Other Divisions
1. Division 16000 – Power Circuiting
2. Division 15400 – Plumbing
D. Contractor is responsible for coring and fire-stopping all rated penetrations of the structure.
1.03 SUBMITTALS
A. Product data: within 15 calendar days after the Contractor has received the Owner’s Notice to
proceed, submit the following. Refer to Division 1 requirements for copy quantity of
submittals or if not specified submit seven (7) copies.
1. Coordinated shop drawings, showing proposed layout of equipment, piping, ducts,
registers, grilles, controls, and other components of the system. Ductwork shop drawings
shall be done at ¼” =1’-0”. Submit cut sheets on ductwork, connections, fittings, air
terminals, fire dampers, etc…
2. Submit schematic control diagram showing all control components, wiring, and locations.
Control submittal shall also include sequence of operation for each system.
3. Manufacturer catalogs, samples, and other items needed to fully demonstrate the quality
of the proposed materials and equipment. In addition to the submittals formerly mention
herein equipment specification sheets and dimensional data on the following:
a. Packaged heat recovery unit.
b. Fan coil units.
c. Unit ventilators.
d. Temperature controls.
e. Boilers.
f. Insulation.
g. Piping, flue and vent piping and accessories.
h. Grilles, registers, and diffuser.
B. Record Drawings
1. Include a copy of the record drawings (as-builts) in each copy of the operation and
maintenance manual described below.
C. Testing and Balancing Reports
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 4
1. Submit four (4) copies of a certified testing and balancing report to the Architect for
review and approval. Include all airflow and temperature readings as outlined herein.
D. Operating Instructions
1. Prior to the completion of all work and the final inspection of the installation by the
Owner, three (3) copies of a complete Instruction Manual, bound in booklet form and
suitably indexed, shall be submitted to the Architect for review and approval. All written
material contained in the manual shall be typewritten or printed.
1.04 INSTRUCTION OF OWNER’S PERSONNEL
A. After completion of all work and all tests and at such time as designated by the Owner,
provide the necessary skilled personnel to operate the entire installation for a period of
sixteen (16) hours.
B. During the operating period, fully instruct the Owner’s representative in the complete
operation, adjustment and maintenance of the entire installation.
1.05 QUALITY ASSURANCE
A. Use adequate numbers of skilled workmen who are thoroughly trained and experienced in the
necessary crafts and who are completely familiar with the specified requirements and the
methods needed for proper performance of the work in this section.
B. The Contractor’s superintendent shall conduct all coordination between the Contractor, the
Architect, the Engineers, etc., and shall fully represent the Contractor’s position in his
absence. All decisions by the superintendent shall become the responsibility of the
Contractor and binding to the Contract. The Contractor shall be responsible for the drawings,
and that which is written or implied in the specifications.
C. Without additional cost to the Owner, provide such other labor and materials as are required
to complete the work of this Section in accordance with the requirements of governmental
agencies having jurisdiction, regardless of whether such materials and associated labor are
called for elsewhere in these Contract Documents.
D. Before submitting the final proposal examine the site of the proposed work to determine
existing conditions that may effect the work, as this section will be help responsible for any
assumption in regard thereto.
1.06 GUARANTEE
A. The Contractor shall guarantee every component part of each system for a minimum of one-
year parts and labor. The contractor shall also provide the Owner with factory warranties for
all equipment. For equipment with compressors, provide extended five-year warranty on
entire sealed system.
PART 2 – PRODUCTS
2.01 DUCTWORK
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 5
A. For the HVAC systems, provide galvanized sheet metal ducts fabricated and installed to
pertinent ASHRAE and SMACNA standards, except as otherwise indicated. Galvanized
ductwork shall conform to ASTM A527 (G-90) having not less than 1.25 oz. Of zinc on each
side of each square foot of sheet. Duct systems shall comply with the pressure velocity
classification in compliance with the SMACNA HVAC Duct construction Standards, 1985
first edition. Minimum pressure classifications shall be 2” w.g.
B. Design all ductwork using the equal friction method. For all areas, the ductwork shall be
designed to not exceed 0.1”/100’.
C. Furnish and install the size, connections and run of ducts as indicated on the drawings.
Drawings indicate inside clear dimensions.
D. The sheet metal ductwork shall, whether indicated or not, rise and drop and change in shape
to clear lighting fixtures, plumbing and structural framing etc., to maintain the desired
clearances within the spaces.
E. The ductwork shall be continuous with airtight joints and seams presenting a smooth surface
on the inside and neatly finished on the outside. Ducts shall be constructed with curves and
bends so as to effect an easy flow of air. Unless otherwise shown on the Drawings, the inside
radius of all curves and bends shall be not less than width of ducts in plane of bend.
F. All ductwork, unless otherwise noted, shall be built from galvanized sheet steel thoroughly
braced and stiffened. All ductwork shall be of the gauge recommended by SMACNA except
that the minimum gauge thickness for any duct shall be no less than 24.
G. Seal all ducts seams, transverse and longitudinal, air tight with 3M “ED800” or equal duct
sealing compound.
H. At branch ducts, provide manually operated dampers of the type and arrangement shown on
the Drawings, two gauges heavier that the duct in which installed and equipped with locking
quadrants. All branch take-offs shall be made with 45 or full Bellmouth type fittings.
I. Volume dampers, provide single and multi blade manually adjustable dampers as shown on
drawings in all duct splits and branch connection of supply and exhaust air systems.
J. Turning vanes, provide and install airfoil vanes at square duct elbows and as noted on
drawings. Vane length not to exceed 36 inches. Provide separate equal size sections for
greater lengths.
K. Flexible duct shall be 1” thick insulated low pressure type with vapor barrier as manufactured
by Automation Industries. Thermoflex type MKE or equal. Maximum length of flex duct is
5 feet. Secure with tie straps screwed to duct and duct sealer. Flexible ductwork shall only
be allowed at connections to diffusers, registers, and grilles where the ductwork is located
above an acoustical ceiling.
L. Fire Dampers
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 6
1. Construction: UL listed and rated for 1-1/2 hour fire rating in conformance with NFPA
90A and authorities having jurisdiction. All shall be out-of-stream type.
2. Provide fire dampers with access doors in openings in the following locations.
a. Fire rated wall and fire partition.
b. Fire rated ceilings and floors.
c. When required by local and state codes.
2.02 AIR OUTLETS
A. Diffusers, registers, and grilles shall be provided in sufficient quantity and location to
adequately diffuse, return and/or exhaust air over the entire zone being serviced.
Manufacture’s shall be Titus, Krueger, or MetalAire.
B. Supply registers serving the areas without acoustical ceilings shall be double deflection type
similar to Titus Model #301RS. Ceiling diffusers as specified herein may also be used in
areas where sidewall supply registers cannot provide adequate air diffusion and coverage
such as narrow corridors. Return and exhaust registers in all spaces shall be fixed deflection
type similar to Titus Model #350FL (aluminum in bathroom areas). All supply and exhaust
registers shall have opposed blade dampers. Where the branch duct damper leading to a
return grille is not readily accessible the grille shall be provide with an opposed blade
damper.
C. Ceiling supply diffusers shall be lay-in module type in acoustical ceiling areas, surface mount
in all other areas. Diffusers shall have adjustable pattern blades and shall be similar to Titus
Model #TDCA. All diffusers shall have opposed blade dampers.
D. On return grilles/registers in the acoustical ceiling areas, provide a sound line plenum box the
full duct dimension of the grille/register shall be provided for the connection to the branch
duct. For square neck supply diffusers connecting to a round duct, the transition piece shall
have a minimum 45 degree angle.
E. For all diffusers, registers, and grilles select so as not to exceed a noise criteria of 28.
2.03 PIPE AND FITTINGS
A. All pipes shall be new, free from scale or rust, of the material and weight specified under the
various services. Each length of pipe shall be properly marked at the mill or proper
identification with name or symbol of manufacturer.
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 7
B. All copper tubing shall be of weight as required for services specified, with conformance with
ASTM B-88 for types “L” and “K” tubing, as manufactured by Chase, Anaconda, Revere, or
an approved equal. Tubing and fittings shall be thoroughly cleaned with sand cloth and
treated with an approved non-corrosive flux before solder is applied.
C. Combustion air and flue vent piping from condensing furnace shall be schedule 40 CPVC
pipe. At floor penetrations and other penetrations of rated structure provide expanding fire
stop collars listed to protect plastic pipe openings as manufactured by 3M or approved equal.
D. All condensate piping shall have serviceable traps. Where condensate from a roof-top unit is
within 10 feet of a roof drain, run line to roof drain otherwise provide concrete splash block
under outlet.
2.04 PIPE FOR VARIOUS SERVICES
A. Solder for each solder type fitting shall be 95% tin and 5% antimony.
B. Pipe Schedule:
Service - Piping Type Piping Sch. WT. Notes
*Refrigerant Piping ACR hard drawn. ACR Type K Silver-brazed joints
Condensate Piping Hard Drawn Type L
*Provide liquid line filer drier and sight glass on each circuit.
2.05 INSULATION
A. General
1. Provide materials complying with NFPAS bulletin 90-A, as determined by UL method
NFPA 225-ASTM E 84 and complying with the governing code, with flame spread rating
under 25 and smoke developed rating under 50.
2. Where vapor barriers are used, provide intact and continuous throughout.
3. Acceptable manufacturers: Owes/Corning Fiberglass, Manville, or Certainteed
B. Supply Return & Return Air Ductwork: The following ductwork shall be insulated:
1. All supply air ductwork except that exposed within the space it serves. Supply air
ductwork located in a ceiling return air plenum must be insulated.
2. All return air ductwork. Return air ductwork located within a ceiling return air plenum or
located within a ceiling cavity sandwiched between two conditioned areas (i.e. return
duct above first floor ceiling and below 2nd floor slab) need not be externally insulated.
Return air ductwork in attic areas or in machine rooms must be insulated.
3. Return and exhaust air ductwork from the discharge point to the back draft or isolation
damper (see outdoor air ductwork).
Above ductwork shall be insulated with 1 ½” thick flexible blanket duct insulation with vapor
barrier, .75 lbs. Per cubic foot density glass fiber with maximum K factor of 0.28 at 75 degree
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 8
F. mean temperature with fire retardant foil/draft vapor barrier facing. Product shall be
Owens Corning FRK type 75 or equal. All seams and joints shall be taped with matching
Kraft paper vapor barrier tape. Exposed supply and return ductwork located within the
conditioned space need not be insulated.
C. Outdoor Air Ductwork: All outdoor air ductwork including combustion air ductwork and
outdoor and relief/exhaust air louver plenums shall be insulated with 2” thick flexible blanket
duct insulation with vapor barrier, 1.5 lbs. Per ft. density glass fiber with maximum K factor
of 0.28 at 75 degree F. mean temperature with fire retardant foil/draft vapor barrier facing.
D. Acoustic insulation: All supply and return ducts shall be lined internally with 1” Insulacoustic
liner for a minimum of 15 feet from the equipment. Liner shall have a smooth microbe
resistant surface in compliance with NFPA and ASHRAE. Duct dimensions noted on
drawings are clear inside dimensions.
E. Insulate all new hot water/chilled water piping with closed cell Armaflex pipe insulation with
all joints and seams glued vapor tight. Minimum wall thickness shall be 1”. Apply UV
protectant sealant over all insulation exposed to the weather.
F. Piping Insulation: Condensate piping located above ceiling and in unconditioned spaces such
as attics shall be insulated as specified above for refrigerant suction lines.
2.06 VIBRATION ISOLATION AND FLEXIBLE CONNECTIONS
A. At duct connections to equipment, provide glass-fabric flexible neoprene connections with a
minimum of 6 inch full length and approved by the governmental agencies having
jurisdiction.
B. At refrigerant pipe connections to chiller and condenser provide braided bronze flexible pipe
connectors as manufactured by Mercer Rubber Co. model # BBF, or equal.
2.07 EXHAUST FANS
A. Exhaust fans shall be of the type and capacity shown on the Drawings; Greenheck, Carnes,
Penn, or equal. Fan shall be tested in accordance with AMCA and bear the AMCA Certified
Performance Rating Seal; fans shall be UL listed. All fans shall come equipped with factory
wired and mounted disconnect switches and back draft dampers.
B. Centrifugal roof exhaust fans for bathroom exhaust shall be heavy gauge aluminum mounted
on a rigid support structure to provide minimal resistance to air flow and minimal noise
generation. Fan wheel shall be of the aluminum backward curved centrifugal type belt driven
Motorized backdraft dampers shall be provided on each roof exhaust fan. Backdraft damper
shall lbe interlocked with operation of exhaust fan to open fully, or modulate as specified,
upon fan activation and close completely when fan is disabled. If dampers are not shown
connected on the electrical plans, this contractor shall hire the project electrician to wire the
dampers to interlock with fan operation. Fans shall come with a factory wired and mounted
disconnect switch (weatherproof as required.).
C. Ceiling exhaust fans shall be forward curved centrifugal wheel direct drive. Motor an dfan
shall be removable from housing, motor shall have ball bearings and have built in overload
protection. Housings shall be steel with acoustic insulation; provide ceiling grille. Provide
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 9
factory mounted disconnect switch and backdraft dampers. Mount ceiling exhaust fan such
that structure above supports the weight of the fan, not the ceiling system. Coordinate
interlock of motorized dampers with electrical contractor.
2.08 ELECTRICAL WORK
A. The HVAC Contractor shall provide all wiring for the Automatic Temperature Controls for
the make-up air unit and all new fan coil units, exhaust fans, unit ventilators, and boilers.
B. The HVAC Contractor shall hire a licensed electrician to perform all control wiring as
required by code. Minimum gauge of all control wiring is 18AWG. All control wiring shall
be plenum rated.
C. The Electrical Contractor shall install and do all power wiring for all motor starter and un-
mounted motors, furnished to him a the job site by other trades.
D. For all low voltage motors, temperature control wiring and motor control wiring, including
wiring for interlocking, shall be provided by the Section providing motors, including the
installation of all control devises.
E. Furnish all starters and all motor control devices for motor driven equipment required for the
work. The Electrical Contractor shall provide all code required disconnect switches for all
motors, except where otherwise noted. The setting of all motors required for mechanical
equipment shall be included as part of the mechanical work.
F. Equipment which includes a number of correlated electrical control devices mounted in a
single enclosure or on a common base with equipment, shall be supplied for installation
completely wired as a unit with terminal boxes and ample leads ready for external wiring.
G. All electrical items called for as part of the mechanical work shall conform to NEMA
Standards, to the requirements of the National Fire Protection Association and to the
requirements of any local electrical code authority having jurisdiction. Any field
modifications required to ensure such conformance shall be included as part of the
mechanical work.
2.09 ELECTRIC MOTORS
A. This Contractor shall provide all electric motors necessary for driving all motor driven
equipment required to be furnished under this section of the Specification.
B. All motors shall be designed for 3 phase, 60 cycle alternating current operation with 208 volts
across the motor terminals, except that, unless otherwise specified herein, all motors 1/3 HP
and smaller shall be designed for single phase, 60 cycle alternating current at 120 volts across
the terminals.
C. The speed, horsepower, type and other essential data for each motor, if not given under
paragraphs describing the various motor driven apparatus, or in schedules on the drawings
shall be submitted to the Engineer for his/her review. All two speed motors shall be single
winding type.
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 10
D. Contractor shall furnish premium efficient motors eligible for rebate by the local electric
utility, when applicable.
2.10 AUTOMATIC TEMPERATURE CONTROLS
A. Furnish and install all control components necessary to obtain a fully functional control
system as described herein. The contractor is responsible for providing all controls, relays,
etc. necessary to accomplish the Sequence of Operations and performance specified, whether
or not the items are specifically identified herein. Wherever a setpoint is referred to, this
implies that the setting is adjustable by the user.
B. The HVAC contractor shall coordinate with the electrical contractor and pay for all electrical
power service required to supply the required power voltage to the control systems if not
shown on the electrical drawings. All low voltage control wiring shall be minimum of 18
AWG plenum rated. All wiring shall run concealed within walls and ceilings.
C. For each of the roof top HVAC units provide a programmable thermostat control system as
specified herein by Honeywell. Coordinate exact location of thermostats with Owner.
D. HVAC contractor shall install duct smoke detectors furnished by the Electrical Contractor.
HVAC contractor shall wire duct smoke detector to unit circuit to shutdown fan and unit
upon activation. Electrical contractor shall power wire duct smoke detector and wire to fire
alarm system. Duct smoke detectors shall be installed on all make-up air and roof-top units
of 2000 cfm or greater in capacity.
2.11 SEQUENCE OF OPERATION
A. Each new fan coil unit and unit ventilators shall be fitted with two way control valves and a
dedicated wall thermostat. Units to connect to the building control system and run in the
occupied and cycle in the un-occupied mode.
B. Heat recovery unit
1. TYPICAL ENERGY RECOVERY VENTILATOR (ERV) CONTROL
a. Energy recovery ventilator is a modular air handling unit with an enthalpy heat
recovery wheel. The system is designed as heating/cooling, single duct, constant
air volume, constant discharge air temperature system utilizing 100% outside air.
The air handling unit includes a supply fan, exhaust fan and enthalpy wheel
motor/drive assembly.
b. The unit shall operate either in the Occupied Mode or Unoccupied Mode.
c. Occupied Mode:
1. During the occupied mode of operation the unit’s supply fan, exhaust fan
and enthalpy wheel drive motor shall run to provide conditioned air to
the occupied zone.
2. Discharge air temperature control shall come under control of the BAS.
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 11
d. Unoccupied Mode:
1. The Unoccupied Mode shall commence at the pre-programmed
unoccupied start time. During the unoccupied mode, the unit’s supply
fan, exhaust fan and enthalpy wheel drive motor shall de-energize and
the outdoor air and exhaust air dampers shall close.
e. Unit operation:
1. The BAS shall index the unit between modes of operation
(occupied/unoccupied) by a time schedule.
2. Unit start/stop shall also be manually selectable through the BAS.
3. Once the unit is indexed into the occupied mode of operation the supply
fan and exhaust fan shall be enabled and the enthalpy wheel drive motor
shall energize. Air handling unit an outside air damper interlocked with
the supply fan and an exhaust damper interlocked with the exhaust fan.
Before either fan is allowed to start both damper shall be fully open as
proven by end switches. Whenever the fans stop all dampers shall close.
4. If a fan failure occurs at the supply fan, exhaust fan or enthalpy wheel
drive motor, as detected by a current switches at each motor, the fans are
stopped, outside air and exhaust air dampers shall close, and as alarm is
generated at the BAS. This interlock is disabled for 30 seconds
(adjustable) after the unit is initially commanded to start. Fans are
locked out until manually reset through the BAS.
f. System volume control:
1. System operates at a constant speed/constant volume.
g. AHU discharge air temperature is controlled through the BAS with temperature
sensors.
h. Heating coil temperature control:
1. The air handling unit has a hot water heating coil with a dedicated freeze
pump (HWP). Coil discharge air temperature controller, with averaging
type sensor, modulates the fail-open 2-way modulating control valve to
maintain discharge air temperature setpoint (70 degrees F adjustable).
2. Hot water coil freeze protection pump control:
a. During the occupied mode, enable freeze protection pump
whenever the outdoor air temperature is below 45 degree F
(adjustable).
b. During the unoccupied mode, enable freeze protection pump
whenever the outdoor air temperature is below 40 degrees F
(adjustable).
c. Freeze protection pump status: BAS shall monitor freeze
protection pump status via differential pressure switch. If the
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 12
pump fails, generate a critical alarm at the BAS and fully open
the water coil 2-way control valve.
3. Temperature low limit switch at entering side of supply fan de-energizes
unit supply and exhaust fans, closes outside air and exhaust dampers, de-
energized the enthalpy wheel drive motor opens 100% the water control
valve to coil when air temperature falls below 38 degrees F (adjustable).
A critical alarm shall be indicated at the BAS.
i. Coil temperature control:
1. The air handling unit has a cooling coil. Coil discharge air temperature
controller, with averaging type sensor, modulates the fail-closed
modulating control valve to maintain discharge air temperature setpoint
(65 degrees F, adjustable).
2. Temperature low limit switch at entering side of supply fan de-energizes
unit supply and exhaust fans, closes outside air and exhaust dampers, de-
energized the enthalpy wheel drive motor opens 100% the water control
valve to coil when air temperature falls below 38 degrees F (adjustable).
A critical alarm shall be indicated at the BAS.
j. BAS shall monitor the intake damper open and closed positions through damper
end switches. In the event the damper closes in a non-alarm condition, stop
supply fan, close outdoor air damper and initiate an alarm at the BAS.
k. Defrost Control
1. Defrost Control: The BAS shall monitor the air temperature leaving the
enthalpy wheel in the make-up air stream (between enthalpy wheel and
the heating & cooling coils). When the air temperature falls below 32
degrees F (adjustable) the supply fan shall be de-energized to defrost the
heat wheel. Once the temperature rises above 35 degrees F (adjustable)
the supply fan shall be energized and continue normal operation.
l. Economizer Control: The ERV has a bypass damper around the energy recovery
wheel in the make-up air stream. The damper shall normally be in the closed
position, forcing all of the outdoor air through the energy wheel. When the
outdoor air enthalpy is below the economizer change-over value the bypass
damper shall open and the energy wheel shall de-energize, allowing 100%
outdoor air to the system for economizer cooling.
m. Filter bank differential pressure:
1. The AHU is equipped with three (3) filter banks: 30% supply pre-filters,
90% bag filters and 30% exhaust filters. A pressure differential
indicating sensor across the filter banks shall indicate an alarm at the
BAS for high or low pressure conditions. Provide independent
transmitters for each individual filter bank.
n. Smoke control:
PERFORMANCE SPECIFICATION James House
Northampton, MA
HVAC 15600- 13
1. Smoke detectors are located in the supply and exhaust/return duct of the
air handling unit as indicated on the plans.
2. A hardwire auxilliary contact on the fire alarm control panel, upon
detection of smoke in the airstream and/or upon a signal from fire alarm
in the event of alarm within the zone, stops air handling unit supply and
exhaust fans and closes the outside air and exhaust dampers. All
shutdowns shall be hardwired interlocked and shall not rely on control
system programming.
END OF SECTION 15600