Attachment 20 - Section 237313 - Central Station Air Handling Units.pdf

16.31.001 / FAA Hangers 8 and 9 Addm. #2 Dated 8/14/17

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SECTION 237313 - CENTRAL-STATION INDOOR AIR-HANDLING UNITS

PART 1 - GENERAL

1.1 RELATED DOCUMENTS

A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section.

1.2 SUMMARY

A. Section Includes:

1. Variable-air-volume, single-zone air-handling units, indoor.

1.3 PERFORMANCE REQUIREMENTS

A. Structural Performance: Casing panels shall be self-supporting and capable of withstanding 133 percent of internal static pressures indicated, without panel joints exceeding a deflection of L/200 where "L" is the unsupported span length within completed casings.

1.4 ACTION SUBMITTALS

A. Product Data: For each air-handling unit indicated.

1. Unit dimensions and weight.

2. Cabinet material, metal thickness, finishes, insulation, and accessories.

3. Fans:

a. Certified fan-performance curves with system operating conditions indicated.

b. Certified fan-sound power ratings.

c. Fan construction and accessories.

d. Motor ratings, electrical characteristics, and motor accessories.

4. Certified coil-performance ratings with system operating conditions indicated.

5. Dampers, including housings, linkages, and operators.

6. Filters with performance characteristics.

1.5 INFORMATIONAL SUBMITTALS

A. Coordination Drawings: Floor plans and other details, drawn to scale, on which the following items are shown and coordinated with each other, using input from installers of the items involved:

1. Mechanical-room layout and relationships between components and adjacent structural and mechanical elements.

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2. Support location, type, and weight.

3. Field measurements.

1.6 CLOSEOUT SUBMITTALS

A. Operation and Maintenance Data: For air-handling units to include in emergency, operation, and maintenance manuals.

1.7 MAINTENANCE MATERIAL SUBMITTALS

A. Furnish extra materials that match products installed and that are packaged with protective covering for storage and identified with labels describing contents.

1. Filters: One set(s) for each air-handling unit.

2. Gaskets: One set(s) for each access door.

1.8 QUALITY ASSURANCE

A. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, by a qualified testing agency, and marked for intended location and application.

B. NFPA Compliance: Comply with NFPA 90A for design, fabrication, and installation of air-handling units and components.

C. ARI Certification: Air-handling units and their components shall be factory tested according to ARI 430, "Central-Station Air-Handling Units," and shall be listed and labeled by ARI.

D. ASHRAE Compliance: Applicable requirements in ASHRAE 62.1, Section 5 - "Systems and Equipment" and Section 7 - "Construction and Startup."

E. ASHRAE/IESNA 90.1 Compliance: Applicable requirements in ASHRAE/IESNA 90.1, Section 6 - "Heating, Ventilating, and Air-Conditioning."

F. Comply with NFPA 70.

1.9 COORDINATION

A. Coordinate sizes and locations of concrete bases with actual equipment provided.

B. Coordinate sizes and locations of structural-steel support members, if any, with actual equipment provided.

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PART 2 - PRODUCTS

2.1 MANUFACTURERS

A. Manufacturers: Subject to compliance with requirements, provide products by the following:

1. Temtrol.

2. Trane Custom.

3. Venmar.

4. York Custom.

2.2 UNIT CASINGS

A. General Fabrication Requirements for Casings:

1. Forming: Form walls, roofs, and floors with at least two breaks at each joint.

2. Casing Joints: Sheet metal screws or pop rivets.

3. Sealing: Seal all joints with water-resistant sealant.

4. Casing Coating: Galvanized for indoor units, powder baked enamel for outdoor units.

5. Airstream Surfaces: Surfaces in contact with the airstream shall comply with requirements in ASHRAE 62.1.

B. Casing Insulation and Adhesive:

1. Materials: ASTM C 1071, Type I or Type II.

2. Location and Application: Encased between outside and inside casing.

C. Inspection and Access Panels and Access Doors:

1. Panel and Door Fabrication: Formed and reinforced, single- or double-wall and insulated panels of same materials and thicknesses as casing.

2. Maintenance and Pipe Vestibule:

a. Entire Length of unit.

b. Size: Large enough to allow inspection and maintenance of air-handling unit's internal components.

3. Inspection and Access Panels:

a. Fasteners: Two or more camlock type for panel lift-out operation. Arrangement shall allow panels to be opened against air-pressure differential.

b. Gasket: Neoprene, applied around entire perimeters of panel frames.

c. Size: Large enough to allow inspection and maintenance of air-handling unit's internal components.

4. Access Doors:

a. Hinges: A minimum of two ball-bearing hinges or stainless-steel piano hinge and two wedge-lever-type latches, operable from inside and outside. Arrange doors to be opened against air-pressure differential.

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b. Gasket: Neoprene, applied around entire perimeters of panel frames.

c. Fabricate windows in fan section doors of double-glazed, wire-reinforced safety glass with an air space between panes and sealed with interior and exterior rubber seals. Include test port.

d. Size: At least 10 inches wide by 10 inches high.

5. Locations and Applications:

a. Fan Section: Doors.

b. Access Section: Doors.

c. Coil Section: Inspection and access panel.

d. Damper Section: Doors.

e. Filter Section: Doors large enough to allow periodic removal and installation of filters.

f. Mixing Section: Doors.

g. Humidifier Section: Doors.

6. Service Light: 23-W compact fluorescent vapor proof fixture with switched junction box located outside adjacent to door.

a. Locations: Each section accessed with door.

D. Condensate Drain Pans:

1. Fabricated with minimum one percent slope in at least two planes to collect condensate from cooling coils (including coil piping connections, coil headers, and return bends) and from humidifiers and to direct water toward drain connection.

a. Length: Extend drain pan downstream from leaving face to comply with

ASHRAE 62.1.

b. Depth: A minimum of 2 inches deep.

2. Formed sections.

3. Double-wall, stainless-steel sheet with space between walls filled with foam insulation and moisture-tight seal.

4. Drain Connection: Located at lowest point of pan and sized to prevent overflow.

Terminate with threaded nipple on one end of pan.

a. Minimum Connection Size: NPS 1.

5. Units with stacked coils shall have an intermediate drain pan to collect condensate from top coil.

E. Air-Handling-Unit Mounting Frame: 4 inch structural steel tube at air handlers, 6 inch structural steel tube for roof top units designed for low deflection, welded with integral lifting lugs.

2.3 FAN, DRIVE, AND MOTOR SECTION

A. The FANWALL Array shall consist of multiple, direct driven plenum fans (Belt driven fans are not acceptable) spaced in the air way tunnel cross section to provide a uniform air flow and velocity profile across the entire air way tunnel cross section and components contained

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therein. The FANWALL Array shall be constructed per AMCA requirements for the duty specified, (Class III). All fans shall be selected to deliver design air flow at the specified operating TSP at the specified motor speed and as scheduled. The FANWALL Array shall be selected to operate at a system Total Static Pressure that does not exceed 90% of the specified fan’s peak static pressure producing capability at the specified fan speed. The (Supply Air or Return Air) FANWALL Array shall be provided with a Coplanar Silencer for sound absorption. The Coplanar Silencers (sound attenuators) will reduce the bare fan discharge sound power levels as noted below and/or in the plans. If NOT otherwise specified, the acoustical silencers shall reduce the bare fan discharge sound power levels by a minimum of 15 db, re 10^-12 watts with center frequencies of 125, 250, 500, 1000, 2000, 4000, and 8000 HZ when compared to the same Air Handling Unit without the silencers.)

B. Each fan motor shall be individually wired to a control panel containing a single VFD as the primary VFD and a backup VFD wired in bypass for each fan motor (Addm. #1), as specified elsewhere. Each VFD shall be sized for the total connected HP for all fan motors contained in the fan array connected (Addm. #1). Wire sizing shall be determined, and installed, in accordance with applicable NEC standards and local code requirements. When specified and scheduled, the multiple fan array electrical panel shall include system optimization controls to actively control fan speed and to enable and disable fans in the multiple fan array. The number of active fans in the array shall be automatically determined, and the speed of the enabled fans shall be adjusted to produce the required coincidental flow and pressure at the perimeter boundary of the unit at substantially peak efficiency. The system optimization controls shall continuously monitor required flow and pressure and shall automatically optimize the operating array configuration and speed for peak efficiency. When specified, system, optimization controls shall be provided that will interface with, and be compatible with the BAS as specified elsewhere. It is the responsibility of the contractor to assure that the fan system optimization controls are compatible with the BAS system. System optimization controls shall be provided by the AHU unit manufacturer to assure single source responsibility for fan volume controls, and shall require only an input control signal from the controls contractor for SP or flow for proper operation of the system optimization controls. When specified, the AHU unit manufacturer shall provide a single communication interface with the BAS and shall coordinate with the controls contractor to make sure that all necessary data points are communicated.

C. Fan and Drive Assemblies: Statically and dynamically balanced and designed for continuous operation at maximum-rated fan speed and motor horsepower.

1. Shafts: Designed for continuous operation at maximum-rated fan speed and motor horsepower, and with field-adjustable alignment.

a. Turned, ground, and polished hot-rolled steel with keyway. Ship with a protective coating of lubricating oil.

b. Designed to operate at no more than 70 percent of first critical speed at top of fan's speed range.

D. Plenum Fan Housings: Steel frame and panel; fabricated without fan scroll and volute housing.

E. Airfoil, Centrifugal Fan Wheels: Smooth-curved inlet flange, backplate, and hollow die-formed airfoil-shaped blades continuously welded at tip flange and backplate; cast-iron or cast-steel hub riveted to backplate and fastened to shaft with set screws.

F. Fan Shaft Bearings:

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1. Grease-Lubricated Bearings: Self-aligning, pillow-block-type, ball or roller bearings with adapter mount and two-piece, cast-iron housing with grease lines extended to outside unit.

G. Internal Vibration Isolation : Fans shall be factory mounted with manufacturer's standard vibration isolation mounting devices having a minimum static deflection of 2 inches.

H. Motor: Comply with NEMA designation, temperature rating, service factor, enclosure type, and efficiency requirements for motors specified in Section 230513 "Common Motor Requirements for HVAC Equipment."

1. Enclosure Type: Totally enclosed, fan cooled.

2. NEMA Premium (TM) efficient motors as defined in NEMA MG 1.

3. Motor Sizes: Minimum size as indicated. If not indicated, large enough so driven load will not require motor to operate in service factor range above 1.0.

4. Controllers, Electrical Devices, and Wiring: Comply with requirements for electrical devices and connections specified in electrical Sections.

I. Variable Frequency Controllers for Supply, Return and Regeneration Fans supplied by Controls Contractor Manufacture (Addm. #1):

1. Description: NEMA ICS 2, IGBT, PWM, VFC; listed and labeled as a complete unit and arranged to provide variable speed of an NEMA MG 1, Design B, 3-phase induction motor by adjusting output voltage and frequency.

2. Output Rating: 3-phase; 6 to 66 Hz, with torque constant as speed changes.

3. Unit Operating Requirements:

a. Input ac voltage tolerance of 380 to 500 V, plus or minus 10 percent.

b. Input frequency tolerance of 06/11 Hz, plus or minus 6 percent.

c. Minimum Efficiency: 96 percent at 60 Hz, full load.

d. Minimum Displacement Primary-Side Power Factor: 96 percent.

e. Overload Capability: 1.1 times the base load current for 60 seconds; 2.0 times the base load current for 3 seconds.

f. Starting Torque: 100 percent of rated torque or as indicated.

g. Speed Regulation: Plus or minus 1 percent.

4. Isolated control interface to allow controller to follow control signal over an 11:1 speed range.

5. Internal Adjustability Capabilities:

a. Minimum Speed: 5 to 25 percent of maximum rpm.

b. Maximum Speed: 80 to 100 percent of maximum rpm.

c. Acceleration: 2 to a minimum of 22 seconds.

d. Deceleration: 2 to a minimum of 22 seconds.

e. Current Limit: 50 to a minimum of 110 percent of maximum rating.

6. Self-Protection and Reliability Features:

a. Input transient protection by means of surge suppressors.

b. Undervoltage and overvoltage trips; inverter overtemperature, overload, and overcurrent trips.

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c. Adjustable motor overload relays capable of NEMA ICS 2, Class 20 performance.

d. Notch filter to prevent operation of the controller-motor-load combination at a natural frequency of the combination.

e. Instantaneous line-to-line and line-to-ground overcurrent trips.

f. Loss-of-phase protection.

g. Reverse-phase protection.

h. Short-circuit protection.

i. Motor overtemperature fault.

7. Automatic Reset/Restart: Attempts three restarts after controller fault or on return of power after an interruption and before shutting down for manual reset or fault correction.

Bidirectional autospeed search shall be capable of starting into rotating loads spinning in either direction and returning motor to set speed in proper direction, without damage to controller, motor, or load.

8. Power-Interruption Protection: To prevent motor from re-energizing after a power interruption until motor has stopped.

9. Torque Boost: Automatically varies starting and continuous torque to at least 1.5 times the minimum torque to ensure high-starting torque and increased torque at slow speeds.

10. Motor Temperature Compensation at Slow Speeds: Adjustable current fall-back based on output frequency for temperature protection of self-cooled, fan-ventilated motors at slow speeds.

11. Door-mounted LED status lights shall indicate the following conditions:

a. Power on.

b. Run.

c. Overvoltage.

d. Line fault.

e. Overcurrent.

f. External fault.

12. Panel-Mounted Operator Station: Start-stop and auto-manual selector switches with manual-speed-control potentiometer and elapsed time meter.

13. Meters or digital readout devices and selector switch, mounted flush in controller door and connected to indicate the following controller parameters:

a. Output frequency (Hertz).

b. Motor speed (rpm).

c. Motor status (running, stop, fault).

d. Motor current (amperes).

e. Motor torque (percent).

f. Fault or alarming status (code).

g. Proportional-integral-derivative (PID) feedback signal (percent).

h. DC-link voltage (volts direct current).

i. Set-point frequency (Hertz).

j. Motor output voltage (volts).

14. Control Signal Interface:

a. Electric Input Signal Interface: A minimum of 2 analog inputs (0 to 10 V or 0/4-20 mA) and 6 programmable digital inputs.

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b. Remote signal inputs capable of accepting any of the following speed-setting input signals from the control system:

1) 0 to 10-V dc.

2) 0-20 or 4-20 mA.

3) Potentiometer using up/down digital inputs.

4) Fixed frequencies using digital inputs.

5) RS485.

6) Keypad display for local hand operation.

c. Output signal interface with a minimum of 1 analog output signal (0/4-20 mA), which can be programmed to any of the following:

1) Output frequency (Hertz).

2) Output current (load).

3) DC-link voltage (volts direct current).

4) Motor torque (percent).

5) Motor speed (rpm).

6) Set-point frequency (Hertz).

d. Remote indication interface with a minimum of 2 dry circuit relay outputs (120-V ac, 1 A) for remote indication of the following:

1) Motor running.

2) Set-point speed reached.

3) Fault and warning indication (overtemperature or overcurrent).

4) High- or low-speed limits reached.

15. Communications: RS485 interface allows VFC to be used with an external system within a multidrop LAN configuration. Interface shall allow all parameter settings of VFC to be programmed via BMS control. Provide capability for VFC to retain these settings within the nonvolatile memory.

16. Integral Disconnecting Means: NEMA KS 1, nonfusible switch with lockable handle.

17. Accessories:

a. Devices shall be factory installed in controller enclosure unless otherwise indicated.

b. Push-Button Stations, Pilot Lights, and Selector Switches: NEMA ICS 2, heavy-duty type.

c. Standard Displays:

1) Output frequency (Hertz).

2) Set-point frequency (Hertz).

3) Motor current (amperes).

4) DC-link voltage (volts direct current).

5) Motor torque (percent).

6) Motor speed (rpm).

7) Motor output voltage (volts).

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2.4 COIL SECTION

A. General Requirements for Coil Section:

1. Comply with ARI 410.

2. Fabricate coil section to allow removal and replacement of coil for maintenance and to allow in-place access for service and maintenance of coil(s).

3. Coils shall not act as structural component of unit.

2.5 AIR FILTRATION SECTION

A. General Requirements for Air Filtration Section:

1. Comply with NFPA 90A.

2. Provide minimum arrestance according to ASHRAE 52.1, and a minimum efficiency reporting value (MERV) according to ASHRAE 52.2.

3. Provide filter holding frames arranged for flat or angular orientation, with access doors on both sides of unit. Filters shall be removable from one side or lifted out from access plenum.

B. Disposable Panel Filters (prefilter):

1. Factory-fabricated, viscous-coated, flat-panel type.

2. Thickness: 2 inches.

3. Dust-Holding Capacity: .

4. Arrestance (ASHRAE 52.1): 80 .

5. Merv (ASHRAE 52.2): 5 .

6. Media: Interlaced glass fibers sprayed with nonflammable adhesive and antimicrobial agent.

7. Frame: Galvanized steel, with metal grid on outlet side, steel rod grid on inlet side, hinged, and with pull and retaining handles.

C. Extended-Surface, Nonsupported-Media Filters:

1. Factory-fabricated, dry, extended-surface, self-supporting type.

2. Arrestance (ASHRAE 52.1): 95.

3. Merv (ASHRAE 52.2): 13.

4. Media: Fibrous material with antimicrobial agent constructed so individual pleats are maintained in tapered form by flexible internal supports under rated-airflow conditions.

5. Filter-Media Frame: Galvanized steel.

6. Mounting Frames: Welded, galvanized steel, with gaskets and fasteners, suitable for bolting together into built-up filter banks with space for prefilter.

D. Filter Gage:

1. 3-1/2-inch- diameter, diaphragm-actuated dial in metal case.

2. Vent valves.

3. Black figures on white background.

4. Front recalibration adjustment.

5. 2 percent of full-scale accuracy.

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6. Range: 0- to 1.0-inch wg.

7. Accessories: Static-pressure tips with integral compression fittings, 1/4-inch aluminum tubing, and 2- or 3-way vent valves.

2.6 DAMPERS

A. General Requirements for Dampers: Leakage rate, according to AMCA 500, "Laboratory Methods for Testing Dampers for Rating," shall not exceed 2 percent of air quantity at 2000-fpm face velocity through damper and 4-inch wg pressure differential.

B. Electronic Damper Operators:

1. Direct-coupled type designed for minimum 60,000 full-stroke cycles at rated torque.

2. Electronic damper position indicator shall have visual scale indicating percent of travel and 2- to 10-V dc, feedback signal.

3. Nonspring-Return Motors for Dampers Larger Than 25 Sq. Ft.: Size for running torque of 150 in. x lbf and breakaway torque of 300 in. x lbf.

4. Spring-Return Motors for Dampers Larger Than 25 Sq. Ft.: Size for running and breakaway torque of 150 in. x lbf.

5. Size dampers for running torque calculated as follows:

a. Parallel-Blade Damper with Edge Seals: 7 inch-lb/sq. ft. of damper.

b. Opposed-Blade Damper with Edge Seals: 5 inch-lb/sq. ft. of damper.

c. Parallel-Blade Damper without Edge Seals: 4 inch-lb/sq. ft of damper.

d. Opposed-Blade Damper without Edge Seals: 3 inch-lb/sq. ft. of damper.

e. Dampers with 2- to 3-Inch wg of Pressure Drop or Face Velocities of 1000 to 2500 fpm: Increase running torque by 1.5.

f. Dampers with 3- to 4-Inch wg of Pressure Drop or Face Velocities of 2500 to 3000 fpm: Increase running torque by 2.0.

6. Coupling: V-bolt and V-shaped, toothed cradle.

7. Overload Protection: Electronic overload or digital rotation-sensing circuitry.

8. Fail-Safe Operation: Mechanical, spring-return mechanism with external, manual gear release on nonspring-return actuators.

9. Power Requirements (Two-Position Spring Return): 24-V ac.

10. Power Requirements (Modulating): Maximum 10 VA at 24-V ac or 8 W at 24-V dc.

11. Proportional Signal: 2- to 10-V dc or 4 to 20 mA, and 2- to 10-V dc position feedback signal.

12. Temperature Rating: Minus 22 to plus 122 deg F.

13. Run Time: 12 seconds open, 5 seconds closed.

C. Outdoor- and Return-Air Dampers: Low-leakage, double-skin, airfoil-blade, galvanized-steel dampers with compressible jamb seals and extruded-vinyl blade edge seals in parallel-blade arrangement with cadmium-plated steel operating rods rotating in sintered bronze or nylon] bearings mounted in a single galvanized-steel frame, and with operating rods connected with a common linkage. Leakage rate shall not exceed 5 cfm/sq. ft. at 1-inch wg and 9 cfm/sq. ft. at 4-inch wg.

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2.7 CHARACTERISTICS

A. Casing:

1. Outside Casing: Galvanized steel, minimum 16 gauge

2. Inside Casing: Galvanized steel G-90, solid, minimum 20 gauge, 22 gauge perforated in fan section, exhaust box, outside air box and discharge plenum box of indoor air handling units.

3. Middle walls: Galvanized steel G-90, 18 gauge.

4. Floor Plate: 16 gauge G90 galvanized floor with 20 gauge G-90 galvanized inner liner.

5. Insulation Thickness: 3 inches in walls and roof, polyurethane spray (R-20) in floor.

B. Supply Fan:

1. Class III: AMCA 99-2408.

2. Drive: Direct.

3. Type: Aluminum, airfoil centrifugal.

4. VFD: Multiple VFD’s shall be provided to ensure appropriate fanwall turndown.

C. Return, Exhaust and Regeneration Fans:

1. Class III: AMCA 99-2408.

2. Drive: Direct.

3. Type: Aluminum, airfoil centrifugal.

4. VFD: Multiple VFD’s shall be provided to ensure appropriate fanwall turndown.

D. Preheat Coil:

1. Coil Type: Single tube for steam, continuous circuit for hot water.

2. Piping Connections: Threaded, same end of coil.

3. Tube Material: Copper.

4. Tube Thickness: 0.035 in.

5. Fin Type: Plate.

6. Fin Material: Aluminum.

7. Fin Thickness: 0.010.

8. Fin and Tube Joint: Mechanical bond.

9. Headers:

a. Cast iron with drain and air vent tapings extended to exterior of unit.

10. Frames: Channel frame, 16 gauge stainless steel.

11. Coil Working-Pressure Ratings: 200 psig, 325 deg F.

E. Cooling Coil:

1. Coil Type: Continuous circuit.

2. Piping Connections: Threaded, same end of coil.

3. Tube Material: Copper .

4. Tube Thickness: 0.025 inches.

5. Fin Type: Plate.

6. Fin Material: Aluminum.

7. Fin Thickness: 0.008 inches.

8. Fin and Tube Joint: Mechanical bond.

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9. Headers:

a. Cast iron with drain and air vent tapings extended to exterior of unit.

b. Provide insulated cover to conceal headers exposed outside casings.

10. Frames: Channel frame, 16 gauge stainless steel.

2.8 SOURCE QUALITY CONTROL

A. Fan Sound-Power Level Ratings: Comply with AMCA 301, "Methods for Calculating Fan Sound Ratings from Laboratory Test Data." Test fans according to AMCA 300, "Reverberant Room Method for Sound Testing of Fans." Fans shall bear AMCA-certified sound ratings seal.

B. Fan Performance Rating: Factory test fan performance for airflow, pressure, power, air density, rotation speed, and efficiency. Rate performance according to AMCA 210, "Laboratory Methods of Testing Fans for Aerodynamic Performance Rating."

C. Water Coils: Factory tested to 300 psig according to ARI 410 and ASHRAE 33.

D. Steam Coils: Factory tested to 300 psig and to 200 psig underwater according to ARI 410 and

ASHRAE 33.

PART 3 - EXECUTION

3.1 EXAMINATION

A. Examine areas and conditions, with Installer present, for compliance with requirements for installation tolerances and other conditions affecting performance of the Work.

B. Examine casing insulation materials and filter media before air-handling unit installation.

Reject insulation materials and filter media that are wet, moisture damaged, or mold damaged.

C. Examine roughing-in for steam, hydronic, and condensate drainage piping systems and electrical services to verify actual locations of connections before installation.

D. Proceed with installation only after unsatisfactory conditions have been corrected.

3.2 INSTALLATION

A. Equipment Mounting:

1. Install air-handling units on cast-in-place concrete equipment bases. Comply with requirements for equipment bases and foundations specified in Section 033000 "Cast-in- Place Concrete."

2. Comply with requirements for vibration isolation devices specified in Section 230548.13 "Vibration Controls for HVAC."

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B. Arrange installation of units to provide access space around air-handling units for service and maintenance.

C. Do not operate fan system until filters (temporary or permanent) are in place. Replace temporary filters used during construction and testing, with new, clean filters.

D. Install filter-gage, static-pressure taps upstream and downstream of filters. Mount filter gages on outside of filter housing or filter plenum in accessible position. Provide filter gages on filter banks, installed with separate static-pressure taps upstream and downstream of filters.

3.3 CONNECTIONS

A. Comply with requirements for piping specified in other Sections. Drawings indicate general arrangement of piping, fittings, and specialties.

B. Install piping adjacent to air-handling unit to allow service and maintenance.

C. Connect piping to air-handling units mounted on vibration isolators with flexible connectors.

D. Connect condensate drain pans using NPS 1-1/4 , ASTM B 88, Type M copper tubing. Extend to nearest equipment or floor drain. Construct deep trap at connection to drain pan and install cleanouts at changes in direction.

E. Hot- and Chilled-Water Piping: Comply with applicable requirements in Section 232113 "Hydronic Piping" and Section 232116 Hydronic Piping Specialties." Install shutoff valve and union or flange at each coil supply connection. Install balancing valve and union or flange at each coil return connection.

F.

G. Connect duct to air-handling units with flexible connections.

3.4 FIELD QUALITY CONTROL

A. Manufacturer's Field Service: Engage a factory-authorized service representative to inspect, test, and adjust components, assemblies, and equipment installations, including connections.

B. Tests and Inspections:

1. Leak Test: After installation, fill water and steam coils with water, and test coils and connections for leaks.

2. Charge refrigerant coils with refrigerant and test for leaks.

3. Fan Operational Test: After electrical circuitry has been energized, start units to confirm proper motor rotation and unit operation.

4. Test and adjust controls and safeties. Replace damaged and malfunctioning controls and equipment.

C. Air-handling unit or components will be considered defective if unit or components do not pass tests and inspections.

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D. Prepare test and inspection reports.

3.5 STARTUP SERVICE

A. Engage a factory-authorized service representative to perform startup service.

1. Complete installation and startup checks according to manufacturer's written instructions.

2. Verify that shipping, blocking, and bracing are removed.

3. Verify that unit is secure on mountings and supporting devices and that connections to piping, ducts, and electrical systems are complete. Verify that proper thermal-overload protection is installed in motors, controllers, and switches.

4. Verify proper motor rotation direction, free fan wheel rotation, and smooth bearing operations. Reconnect fan drive system, align belts, and install belt guards.

5. Verify that bearings, pulleys, belts, and other moving parts are lubricated with factory-recommended lubricants.

6. Verify that zone dampers fully open and close for each zone.

7. Verify that outdoor- and return-air mixing dampers open and close, and maintain minimum outdoor-air setting.

8. Comb coil fins for parallel orientation.

9. Verify that proper thermal-overload protection is installed for electric coils.

10. Install new, clean filters.

11. Verify that manual and automatic volume control and fire and smoke dampers in connected duct systems are in fully open position.

B. Starting procedures for air-handling units include the following:

1. Energize motor; verify proper operation of motor, drive system, and fan wheel. Adjust fan to indicated rpm.

2. Measure and record motor electrical values for voltage and amperage.

3. Manually operate dampers from fully closed to fully open position and record fan performance.

3.6 ADJUSTING

A. Adjust damper linkages for proper damper operation.

B. Comply with requirements in Section 230593 "Testing, Adjusting, and Balancing for HVAC" for air-handling system testing, adjusting, and balancing.

3.7 CLEANING

A. After completing system installation and testing, adjusting, and balancing air-handling unit and air-distribution systems and after completing startup service, clean air-handling units internally to remove foreign material and construction dirt and dust. Clean fan wheels, cabinets, dampers, coils, and filter housings, and install new, clean filters.

237313 - 15 MODULAR INDOOR CENTRAL-

STATION AIR-HANDLING UNITS

3.8 DEMONSTRATION

A. Train Owner's maintenance personnel to adjust, operate, and maintain air-handling units.

END OF SECTION 237313