Attachment 21 - Section 237416.13-Packaged, Large-Capacity, Rooftop Air-Conditioning Units.pdf

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

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ROOFTOP AIR-CONDITIONING

UNITS

SECTION 237416.13 - PACKAGED, LARGE-CAPACITY, ROOFTOP AIR-CONDITIONING 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 packaged, large-capacity, rooftop air conditioning units (RTUs) with the following components and accessories:

1. Casings.

2. Fans.

3. Motors.

4. Coils.

5. Air filtration.

6. UV germicidal irradiation section.

7. Sound-attenuator section.

8. Dampers.

9. Electrical power connections.

10. Controls.

11. Accessories

12. Roof curbs.

1.3 DEFINITIONS

A. DDC: Direct-digital controls.

B. ECM: Electronically commutated motor.

C. RTU: Rooftop unit. As used in this Section, this abbreviation means packaged, large-capacity, rooftop air-conditioning units. This abbreviation is used regardless of whether the unit is mounted on the roof or on a concrete base on ground.

D. Supply-Air Fan: The fan providing supply air to conditioned space. "Supply air" is defined as the air entering a space from air-conditioning, heating, or ventilating apparatus.

E.

1.4 ACTION SUBMITTALS

A. Product Data: Include manufacturer's technical data for each RTU, including rated capacities, dimensions, required clearances, characteristics, furnished specialties, and accessories.

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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.

7. Factory selection calculations for each antimicrobial ultraviolet lamp installation.

B. Shop Drawings:

1. Include details of equipment assemblies. Indicate dimensions, weights, loads, required clearances, method of field assembly, components, and location and size of each field connection.

2. Include diagrams for power, signal, and control wiring.

1.5 INFORMATIONAL SUBMITTALS

A. Coordination Drawings: 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. Structural members to which RTUs will be attached.

2. Roof openings.

3. Roof curbs and flashing.

1.6 CLOSEOUT SUBMITTALS

A. Operation and Maintenance Data: For RTUs to include in emergency, operation, and maintenance manuals.

1.7 MAINTENANCE MATERIAL SUBMITTALS

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

1. Fan Belts: One set(s) for each belt-driven fan.

2. Filters: One set(s) of filters for each unit.

1.8 COORDINATION

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

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

PART 2 - PRODUCTS

2.1 MANUFACTURERS

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

1. Temtrol.

2. Trane Custom.

3. Venmar.

4. York Custom.

2.2 PERFORMANCE REQUIREMENTS

A. Delegated Design: Engage a qualified professional engineer, as defined in Section 014000

"Quality Requirements," to design mounting and restraints for RTUs, including comprehensive engineering analysis.

1. Design RTU supports to comply with wind performance requirements.

B. Wind-Restraint Performance:

1. Basic Wind Speed: 90 MPH.

2. Building Classification Category: II.

3. Minimum 10 lb/sq. ft multiplied by the maximum area of the mechanical component projected on a vertical plane that is normal to the wind direction, and 45 degrees either side of normal.

2.3 CAPACITIES AND CHARACTERISTICS

A. Exterior Casing Thickness: 0.0626 inch thick.

2.4 CASINGS

A. General Fabrication Requirements for Casings: Formed and reinforced double-wall insulated panels, fabricated to allow removal for access to internal parts and components, with joints between sections sealed.

B. Double-Wall Construction: Fill space between walls with 3 inch foam insulation and seal moisture tight for R-20 performance.

C. Exterior Casing Material: Galvanized steel with factory-painted finish, with pitched roof panels and knockouts with grommet seals for electrical and piping connections and lifting lugs.

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D. Unit shall have full length maintenance and frost protection section, similar to existing RTU’s.

E. Inner Casing Fabrication Requirements:

1. Inside Casing: G-90-coated galvanized steel, 0.034 inch thick.

F. Condensate Drain Pans: Fabricated using stainless 0.025 inches thick steel sheet, a minimum of

2 inches deep, and complying with ASHRAE 62.1 for design and construction of drain pans.

1. Double-Wall Construction: Fill space between walls with foam insulation and seal moisture tight.

2. Drain Connections: Threaded nipple.

G. Airstream Surfaces: Surfaces in contact with the airstream shall comply with requirements in

ASHRAE 62.1.

2.5 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 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

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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:

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.

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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.

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.

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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.

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

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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).

2.6 COILS

A. Supply-Air 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.

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.

11. Condensate Drain Pan: Stainless steel formed with pitch and drain connections.

B. Supply-Air Hydronic Heating 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.

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9. Headers:

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

10. Frames: Channel frame, 16 gauge G-90 galvanized.

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

2.7 AIR FILTRATION

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.

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

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2.8 ANTIMICROBIAL ULTRAVIOLET LAMP SYSTEM

A. Description: Lighting unit installation in rooftop unit with lamps, reflectors, remote water-resistant power supply and cable, and support brackets. Lamps emit 254 nm UV "C" (UVC) band. In metal housing with viewport arranged for and controlled to cycle on and off with cooling coil. Locate downstream of cooling coils and over condensate drain pans.

2.9 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

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common linkage. Leakage rate shall not exceed 5 cfm/sq. ft. at 1-inch wg and 9 cfm/sq. ft. at 4-inch wg.

2.10 ACCESSORIES

A. Duplex, 115-V, ground-fault-interrupter outlet with 15-A overcurrent protection. Include transformer if required. Outlet shall be energized even if the unit main disconnect is open.

B. Filter differential pressure switch with sensor tubing on either side of filter. Set for final filter pressure loss.

C. Remote potentiometer to adjust minimum economizer damper position.

D. Return-air bypass damper.

E. Safeties:

1. Smoke detector.

2. Condensate overflow switch.

3. Phase-loss protection.

4. High pressure control.

F. Hail guards of galvanized steel, painted to match casing.

G. Door switches to disable heating or reset set point when open.

H. Outdoor air intake weather hood with moisture eliminator.

I. Service Lights and Switch: Factory installed in each accessible section with weatherproof cover.

Factory wire lights to a single-point field connection.

2.11 ROOF CURBS

A. Roof curbs with vibration isolators and wind or seismic restraints are specified in

Section 230548 "Vibration and Seismic Controls for HVAC."

B. Materials: Galvanized steel with corrosion-protection coating, watertight gaskets, and factory-installed wood nailer; complying with NRCA standards.

1. Curb Insulation and Adhesive: Comply with NFPA 90A or NFPA 90B.

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

b. Thickness: 2 inches.

2. Application: Factory applied with adhesive and mechanical fasteners to the internal surface of curb.

a. Liner Adhesive: Comply with ASTM C 916, Type I.

b. Mechanical Fasteners: Galvanized steel, suitable for adhesive attachment, mechanical attachment, or welding attachment to duct without damaging liner

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when applied as recommended by manufacturer and without causing leakage in cabinet.

c. Liner materials applied in this location shall have air-stream surface coated with a temperature-resistant coating or faced with a plain or coated fibrous mat or fabric depending on service air velocity.

d. Liner Adhesive: Comply with ASTM C 916, Type I.

C. Curb Dimensions: Height of 14 inches. Adaptable horizontal dimensions as required for existing roof openings.

PART 3 - EXECUTION

3.1 EXAMINATION

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

B. Examine roughing-in for RTUs to verify actual locations of piping and duct connections before equipment installation.

C. Examine roofs for suitable conditions where RTUs will be installed.

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

3.2 INSTALLATION

A. Unit Support: Install unit level on structural steel supports. Coordinate wall penetrations and flashing with wall construction. Secure RTUs to structural support with anchor bolts.

3.3 CONNECTIONS

A. Install condensate drain, minimum connection size, with trap and indirect connection to nearest roof drain or area drain.

B. Install piping adjacent to RTUs to allow service and maintenance.

C. Duct installation requirements are specified in other HVAC Sections. Drawings indicate the general arrangement of ducts. The following are specific connection requirements:

1. Install ducts to termination at top of roof curb.

2. Remove roof decking only as required for passage of ducts. Do not cut out decking under entire roof curb.

3. Connect supply ducts to RTUs with flexible duct connectors specified in Section 233300

"Air Duct Accessories."

4. Install return-air duct continuously through roof structure.

5. Install normal-weight, 3000-psi, compressive strength (28-day) concrete mix inside roof curb, 4 inches thick. Concrete, formwork, and reinforcement are specified with concrete.

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D. Connect electrical wiring according to Section 260519 "Low-Voltage Electrical Power

Conductors and Cables."

E. Ground equipment according to Section 260526 "Grounding and Bonding for Electrical

Systems."

F. Install nameplate for each electrical connection, indicating electrical equipment designation and circuit number feeding connection.

1. Nameplate shall be laminated acrylic or melamine plastic signs as specified in Section

260553 "Identification for Electrical Systems."

2. Nameplate shall be laminated acrylic or melamine plastic signs as layers of black with engraved white letters at least 1/2-inch high.

3. Locate nameplate where easily visible.

3.4 FIELD QUALITY CONTROL

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

B. Perform the following tests and inspections with the assistance of a factory-authorized service representative:

1. After installing RTUs and after electrical circuitry has been energized, test units for compliance with requirements.

2. Inspect for and remove shipping bolts, blocks, and tie-down straps.

3. 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. RTU will be considered defective if it does not pass tests and inspections.

D. Prepare test and inspection reports.

3.5 STARTUP SERVICE

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

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

1. Inspect for visible damage to unit casing.

2. Inspect internal insulation.

3. Verify that labels are clearly visible.

4. Verify that clearances have been provided for servicing.

5. Verify that controls are connected and operable.

6. Verify that filters are installed.

7. Remove packing from vibration isolators.

8. Inspect operation of barometric relief dampers.

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9. Verify lubrication on fan and motor bearings.

10. Inspect fan-wheel rotation for movement in correct direction without vibration and binding.

11. Start unit according to manufacturer's written instructions.

a. Start refrigeration system.

b. Do not operate below recommended low-ambient temperature.

c. Complete startup sheets and attach copy with Contractor's startup report.

12. Inspect and record performance of interlocks and protective devices; verify sequences.

13. Operate unit for an initial period as recommended or required by manufacturer.

14. Calibrate thermostats.

15. Adjust and inspect high-temperature limits.

16. Inspect outdoor-air dampers for proper stroke and interlock with return-air dampers.

17. Inspect controls for correct sequencing of heating, mixing dampers, and normal and emergency shutdown.

18. Measure and record the following minimum and maximum airflows. Plot fan volumes on fan curve.

a. Supply-air volume.

b. Return-air volume.

c. Relief-air volume.

d. Outdoor-air intake volume.

19. Comb coil fins for parallel orientation.

20. After startup and performance testing and prior to Substantial Completion, replace existing filters with new filters.

3.6 CLEANING AND ADJUSTING

A. After completing system installation and testing, adjusting, and balancing RTU and air-distribution systems, clean filter housings and install new filters.

3.7 DEMONSTRATION

A. Train Owner's maintenance personnel to adjust, operate, and maintain RTUs.

END OF SECTION 237416.13