36C24919B0003-0004007.pdf

Replace Satellite chillers Project 603-18-508

Robley Rex VAMC 09-15

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SECTION 23 81 00

DECENTRALIZED UNITARY HVAC EQUIPMENT

PART 1 - GENERAL

1.1 DESCRIPTION

A. This section specifies split-systems (DX Units).

B. Definitions:

1. Energy Efficiency Ratio (EER): The ratio of net cooling capacity is

Btu/h to total rate of electricity input in watts under designated operating conditions (Btu hour/Watt).

2. Seasonal Energy Efficiency Ratio (SEER): The ratio of the total cooling output of an air conditioner during its normal annual usage period for cooling in Btu/h divided by total electric energy input in watts during the same period (Btu hour/Watt).

3. Unitary: A Unitary Air Conditioner consists of one or more factory-made assemblies which normally include an evaporator or cooling coil, a compressor and condenser combination, and may include a heating function as well.

4. Where such equipment is provided in more than one assembly the separated assemblies are to be designed to be used together and the requirements of rating are based upon use of matched assemblies.

1.2 RELATED WORK

A. NA

B. Section 23 05 11, COMMON WORK RESULTS FOR HVAC: General mechanical requirements and items, which are common to more than one section of

Division 23.

C. Section 23 05 41, NOISE and VIBRATION CONTROL FOR HVAC PIPING and

EQUIPMENT: Requirements for different types of vibration isolators and noise ratings in the occupied areas.

D. Section 23 07 11, HVAC and BOILER PLANT INSULATION: Requirements for piping insulation.

E. Section 23 23 00, REFRIGERANT PIPING: Requirements for refrigerant pipes and fittings.

F. NA

G. NA

H. Section 23 74 13, PACKAGED, OUTDOOR, CENTRAL-STATION AIR-HANDLING UNITS:

Requirements for air handling units using chilled water and hot water coils.

I. Section 23 40 00, HVAC AIR CLEANING DEVICES: Requirements for air filtration.

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J. Section 23 08 00 – COMMISSIONING OF HVAC SYSTEMS: Requirements for commissioning, systems readiness checklists, and training.

K. NA

L. Section 23 05 93, TESTING, ADJUSTING, and BALANCING FOR HVAC:

Requirements for testing and adjusting air balance.

1.3 QUALITY ASSURANCE

A. Refer to specification Section 23 05 11, COMMON WORK RESULTS FOR HVAC.

B. Safety Standards: ASHRAE Standard 15, Safety Code for Mechanical

Refrigeration.

1.4 SUBMITTALS

A. Submit in accordance with specification Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, and SAMPLES

B. Manufacturer’s literature and data:

1. Sufficient information, including capacities, pressure drops and piping connections clearly presented, shall be included to determine compliance with drawings and specifications for units noted below:

a. Unitary air conditioners:

1) Self-contained units

2) Split systems

3) Rooftop units

b. Window air conditioners

c. Through-the-wall packaged terminal air conditioning units

d. Gas-Fired Furnaces

2. Unit Dimensions required clearances, operating weights accessories and start-up instructions.

3. Electrical requirements, wiring diagrams, interlocking and control wiring showing factory installed and portions to be field installed.

4. Mounting and flashing of the roof curb to the roofing structure with coordinating requirements for the roof membrane system.

C. Certification: Submit proof of specified ARI Certification.

D. Performance Rating: Submit catalog selection data showing equipment ratings and compliance with required sensible-to-heat-ratio, energy efficiency ratio (EER), and coefficient of performance (COP).

E. Operating and Maintenance Manual: Submit three copies of Operating and

Maintenance manual to Resident Engineer three weeks prior to final inspection.

F. Completed System Readiness Checklists provided by the Commissioning

Agent and completed by the contractor, signed by a qualified technician and dated on the date of completion, in accordance with the requirements of Section 23 08 00 COMMISSIONING OF HVAC SYSTEMS.

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1.5 APPLICABLE PUBLICATIONS

A. The publications listed below form a part of this specification to the extent referenced. The publications are referenced in the text by the basic designation only.

B. Federal Specifications (Fed. Spec.):

A-A-50502-90............ Air conditioner (Unitary Heat Pump) Air to Air

(3000-300,000 Btu)

C. Military Specifications (Mil. Specs.):

MIL-PRF-26915D-06.......Primer Coating, for Steel Surfaces

D. Air-Conditioning, Heating, and Refrigeration Institute (AHRI):

210/240-08..............Performance Rating of Unitary Air-Conditioning and Air-Source Heat Pump Equipment

270-08..................Sound Rating of Outdoor Unitary Equipment

310/380-04..............Standard for Packaged Terminal Air-Conditioners and Heat Pumps (CSA-C744-04)

340/360-07..............Performance Rating of Commercial and Industrial

Unitary Air-Conditioning and Heat Pump Equipment

520-04..................Performance Rating of Positive Displacement

Condensing Units

E. Air Movement and Control Association (AMCA):

210-07..................Laboratory Methods of Testing Fans for

Aerodynamic Performance Rating (ANSI)

410-96..................Recommended Safety Practices for Users and

Installers of Industrial and Commercial Fans

F. American National Standards Institute (ANSI):

S12.51-02(R2007)........Acoustics - Determination of Sound Power Levels of Noise Sources Using Sound Pressure -

Precision Method for Reverberation Rooms (same as ISO 3741:1999)

G. American Society of Heating, Refrigerating, and Air-Conditioning

Engineers (ASHRAE):

2008 Handbook...........HVAC Systems and Equipment

15-10...................Safety Standard for Refrigeration Systems (ANSI)

H. American Society of Testing and Materials (ASTM):

B117-09.................Standard Practice for Operating Salt Spray (Fog)

Apparatus

I. American Society of Civil Engineers (ASCE)

ASCE 7-10...............Minimum Design Loads for Buildings and Other

Structures

J. National Electrical Manufacturer's Association (NEMA):

MG 1-09 (R2010).........Motors and Generators (ANSI)

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ICS 1-00 (R2005, R2008).Industrial Controls and Systems: General

Requirements

K. National Fire Protection Association (NFPA) Publications:

90A-09..................Standard for the Installation of Air-

Conditioning and Ventilating Systems

PART 2 - PRODUCTS

2.1 UNITARY AIR CONDITIONERS - GENERAL

A. Applicable ARI Standards:

1. Cooling Capacity 39.6 kW (135,000 Btu/h) and More: AHRI 340/ 360.

2. Cooling Capacity Less Than 39.6 kW (135,000 Btu/h): AHRI 210/240.

Units shall be listed in the ARI Directory of Certified Unitary Air-

Conditioners.

B. Performance Rating: Cooling capacity of units shall meet the sensible heat and total heat requirements shown in the contract documents. In selecting unit size, make true allowance for "sensible to total heat ratio" to satisfy required sensible cooling capacity.

C. Machinery Guards: Provide guards as shown in AMCA 410 for belts, chains, couplings, pulleys, sheaves, shafts, gears and other moving parts regardless of height above the floor. Drive guards may be excluded where motors and drives are inside factory fabricated casings.

D. Corrosion Prevention: Unless specified otherwise, equipment fabricated from ferrous metals that do not have a zinc coating or a duplex coating of zinc and paint shall be treated for prevention of rust with a factory coating or paint system that will withstand 125 hours in a salt-spray fog test, except that equipment located outdoors shall be tested for 500 hours. The salt-spray fog test shall be in accordance with ASTM B117 using a 20 percent sodium chloride solution. Immediately after completion of the test, the coating shall show no signs of blistering, wrinkling or cracking, no loss of adhesion, and the specimen shall show no signs of rust beyond 3 mm (1/8-inch) on both sides from the scratch mark. For units located in high humidity areas, provide factory-coated coils for protection from corrosion by using multiple stage electro-deposition coating process. Refer to Section 23 82 16, AIR COILS, for additional coil requirements.

2.2 NA

2.3 SPLIT-SYSTEM AIR CONDITIONERS

A. Description: Air handler installed coil, an air-cooled remote condensing unit, and field-installed refrigeration piping.

1. EER: Shall have as a minimum, an EER of 11.5 or the minimum required by ASHRAE 90.1 (latest version); whichever is higher.

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B. Evaporator Components:

1. NA.

2. NA

3. Drain Pans: Galvanized steel, with connection for drain; insulated and complying with ASHRAE 62.1-2007.

4. NA

5. Refrigerant Coil: Copper tube, with mechanically bonded aluminum fins, complying with AHRI 210/240, and with thermal-expansion valve.

6. NA

7. NA

8. NA

9.NA

10. NA

11. NA

C. NA

D. NA

E. NA

F. Air-Cooled, Compressor-Condenser Components:

1. Casing: Steel, finished with baked enamel in color selected by

Architect, with removable panels for access to controls, weep holes for water drainage, and mounting holes in base. Service valves, fittings, and gage ports shall be brass and located outside of the casing.

2. Compressor: Hermetically sealed // reciprocating // scroll // with crankcase heater and mounted on vibration isolation. Compressor motor shall have thermal- and current-sensitive overload devices, start capacitor, relay, and contactor.

3. Compressor motor with manual-reset, high-pressure switch and automatic-reset, low-pressure switch.

4. Refrigerant: R-410A.

5. Refrigerant Coil: Copper tube, with mechanically bonded aluminum fins, complying with AHRI 210/240, and with liquid subcooler.

6. Fan: Aluminum, propeller type, directly connected to motor.

7. Motor: Permanently lubricated, with integral thermal-overload protection.

8. Low Ambient Kit: Permit operation down to minus 18 deg C (0 deg F).

9. Mounting Base: Polyethylene.

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10. Minimum Energy Efficiency: Comply with ASHRAE/IESNA 90.1-2004, "Energy Standard for Buildings except Low-Rise Residential

Buildings."

G. NA

2.4 NA

2.5 NA

2.6 NA

2.7 NA

PART 3 EXECUTION

3.1 INSTALLATION

A. NA.

B. NA

C. NA

D. Install units level and plumb maintaining manufacturer’s recommended clearances and tolerances.

E. NA

F. Install vibration spring isolators under base of self contained unit, with minimum static deflection of 25 mm (1 inch) unless otherwise indicated. Refer to Section 23 05 41, NOISE and VIBRATION CONTROL FOR

HVAC PIPING and EQUIPMENT

G. Install ground-mounting, compressor-condenser components on 100 mm

(4-inch) thick, reinforced concrete base; 100 mm (4 inches) larger on each side than unit. Concrete, reinforcement, and formwork are specified in Section 03 30 00, CAST-IN-PLACE CONCRETE. Coordinate anchor installation with concrete base.

H. Install ground-mounting, compressor-condenser components on polyethylene mounting base.

I. NA

J. NA

K. Install compressor-condenser components on restrained, spring isolators with a minimum static deflection of 25 mm (1 inch) unless otherwise indicated. Refer to Section 23 05 41, NOISE and VIBRATION CONTROL FOR

HVAC PIPING and EQUIPMENT.

L. Install and connect precharged refrigerant tubing to component's quick-connect fittings. Install tubing to allow access to unit.

M. Install wall sleeves in finished wall assembly and weatherproof.

Install and anchor wall sleeves to withstand, without damage seismic forces as required by code.

3.2 CONNECTIONS

A. Verify condensate drainage requirements.

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

C. Install piping adjacent to units to allow service and maintenance.

D. NA

E. NA

F. NA

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

H. NA

I. Ground equipment and install power wiring, switches, and controls for self contained and split systems.

J. Connect refrigerant piping to coils with shutoff valves on the suction and liquid lines at the coil and a union or flange at each connection at the coil and condenser.

K. Install ducts to the units with flexible duct connections.

L. Connect piping with shutoff duty valves on the supply and return side of the coil and unions at all connections and with a throttling valve on the return piping near the coil.

M. Connect piping with shutoff duty valves on the supply and return side of the water cooled condenser and unions at all connections and with a throttling valve on the return piping near the condenser

N. Connect piping with shutoff duty valves and unions on the steam supply and condensate side of the steam coil. On the condensate line near the coil provide a strainer, trap and shutoff valve.

3.3 FIELD QUALITY CONTROL

A. Perform tests and inspections and prepare test reports.

B. Tests and Inspections: After installing units and after electrical circuitry has been energized, test units for compliance with requirements. Inspect for and remove shipping bolts, blocks, and tie-down straps. After electrical circuitry has been energized, start units to confirm proper motor rotation and unit operation. Test and adjust controls and safeties. Replace damaged and malfunctioning controls and equipment. Remove and replace malfunctioning units and retest as specified above.

3.4 INSTRUCTIONS

Provide services of manufacturer’s technical representative for four hours to instruct VA personnel in operation and maintenance of units.

3.5 STARTUP AND TESTING

The Commissioning Agent will observe startup and contractor testing of selected equipment. Coordinate the startup and contractor testing schedules with the Resident Engineer and Commissioning Agent. Provide a minimum of 7 days prior notice.

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3.6 COMMISSIONING

A. Provide commissioning documentation in accordance with the requirements of Section 23 08 00 – COMMISSIONING OF HVAC SYSTEMS for all inspection, start up, and contractor testing required above and required by the

System Readiness Checklist provided by the Commissioning Agent.

B. Components provided under this section of the specification will be tested as part of a larger system. Refer to Section 23 08 00 –

COMMISSIONING OF HVAC SYSTEMS and related sections for contractor responsibilities for system commissioning.

3.7 DEMONSTRATION AND TRAINING

A. Provide services of manufacturer’s technical representative for four hours to instruct VA personnel in operation and maintenance of units.

B. Submit training plans and instructor qualifications in accordance with the requirements of Section 23 08 00 – COMMISSIONING OF HVAC SYSTEMS.

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