Section 15652

SECTION 15652

CENTRAL AIR CONDITIONING EQUIPMENT

PART 1 - GENERAL

1.1 DESCRIPTION OF WORK

A. The works of this Section includes central air conditioning equipment as indicated on the drawings and specified herein.

B. Related Work:

1. Section 01750: Operating and Maintenance Manuals

2. Section 15040: Systems Adjusting, Testing, and Balancing

3. Section 15050: Basic Materials and Methods – Mechanical

1.2 QUALITY ASSURANCE

A. The following codes and standards are intended to provide an acceptable level of quality for materials and products. The Contractor may propose alternative codes and standards provided they give an equivalent degree of quality as the referenced codes and standards. They shall be submitted for the Royal Commission to review in advance of their use.

1. ASHRAE - American Society of Heating Refrigerating and Air Conditioning Engineers:

a. Handbook of Fundamentals

b. Systems and Equipment Volume

c. Applications Volume

d. Réfrigération Volume

e. 15 Safety Code for Mechanical Refrigeration

f. 16 Method of Testing for Rating Room Air Conditioners

g. 52 Method of Testing Air-cleaning Devices Used in General Ventilation for Removing Particulate Matter

EWR-91742 15652-1 Contract No. PIC F – 8129,8140,8141

h. 58 Method of Testing Room Air Conditioner Heating Capacity

2. AMCA - Air Moving and Conditioning Association:

a. 99 Standards Handbook

b. 210 Test Code for Air Moving Devices

c. 300 Test Code for Sound Rating Air Moving Devices

3. ANSI - American National Standards Institute:

a. B 2.1 Pipe Threads (Except Dryseal)

b. B 2.2 Dry seal Pipe Threads

c. B 9.1-1 Safety Code for Mechanical Refrigeration

d. B 15.1 Safety Standard for Mechanical Power Transmission Apparatus

e. B 16.21 Nonmetallic Flat Gaskets for Pipe Flanges

f. B 16.22 Wrought Copper and Copper Alloy Solder Joint Pressure Fittings

g. B 31.5 Refrigeration Piping

h. B 70.1 Refrigeration Flare Type Fittings

i. S 1.21 Methods for the Determination of Sound Power Levels of Small Sources in Reverberation Rooms

j. Z 234.1 Room Air-conditioners

4. ARI - Air-Conditioning and Refrigeration Institute:

a. 210 Unitary Air-conditioning Equipment

b. 240 Air-Source Unitary Heat Pump Equipment

c. 260 Application, Installation and Servicing of Unitary Systems

d. 310 Packaged Terminal Air-conditioners


e. 360 Commercial and Industrial Unitary Air-Conditioning Equipment

f. 410 Forced-Circulation Air-cooling and Air-heating Coils

g. 495 Refrigerant Liquid Receivers

h. 520 Positive Displacement Refrigerant Compressors, Compressor Units and Condensing Units

i. 710 Liquid-line Dryers

j. 760 Solenoid Valves for Use with Volatile Refrigerants

k. Directory of Certified Applied Air Conditioning Products

l. Directory of Certified Unitary Air Conditioners

m. Directory of Certified Unitary Heat Pumps

5. ASTM - American Society for Testing and Materials:

a. A 53 Pipe, Steel, Black and Hot-dipped, Zinc-coated, Welded and Seamless

b. A 167 Stainless and Heat-resisting Chromium-Nickel Steel Plate, Sheet, and Strip

c. A 123 Zinc-coating (Hot-Dip Galvanized) Coating on Iron and Steel Products

d. A 525 Steel Sheet, Zinc-Coated (Galvanized) by the Hot-Dip Process

e. A 527 Steel Sheet, Zinc-Coated (Galvanized) by the Hot-Dip Process, Lock-Forming Quality

f. B 88 Seamless Copper Water Tube

g. B 117 Method of Salt Spray (Fog) Testing

h. B 209 Aluminum-Alloy Sheet and Plate

i. B 210 Aluminum-Alloy Drawn Seamless Tubes


j. B 280 Seamless Copper Tube for Air- Conditioning and Refrigeration Field Service

k. C 534 Preformed Flexible Elastomeric Cellular Thermal Insulation in Sheet and Tubular Form

l. E 84 Test Method for Surface Burning Characteristics of Building Materials

6. NEMA - National Electrical Manufacturers Association:

a. ICS 1 General Standards for Industrial Control and Systems

b. MG 2 Safety Standard for Construction and Guide for Selection, Installation and Use of Electric Motors and Generators

7. NFPA - National Fire Protection Association:

a. 70 National Electrical Code

b. 90 A Installation of Air Conditioning and Ventilating Systems

c. 90 B Installation of Warm Air Heating and Air Conditioning Systems

8. SMACNA – Sheet Metal and Air Conditioning Contractors National Association:

a. Low Pressure Duct Construction Standards

b. High Pressure Duct Construction Standards

9. UL - Underwriters Laboratories:

a. 484 Room Air Conditioners

b. 1096 Electric Central Air Heating Equipment

c. 900 Test Performance of Air Filter Units


1.3 SUBMITTALS

A. Product Data: Submit descriptive literature, on equipment specified itemizing and detailing all relevant data including but not limited to performance capacity charts, tables, and accessories.

B. Shop Drawings: Include the following:

1. Performance capacities and certifications of the unit, fan, and coils.

2. Dimensional data.

3. Unit arrangements and installation layouts, and methods.

4. Unit electrical characteristics and wiring diagrams.

C. Maintenance Manuals: Submit maintenance and operating manuals in accordance with Section 01750.

PART 2 - PRODUCTS

2.1 GENERAL

A. All goods and products covered by these specifications shall be procured, when available, from an in-Kingdom manufacturer. Procurement of all goods and products manufactured out-of-Kingdom must be approved by the Royal Commission.

B. Capacity: The capacity and performance of equipment shall not be less than that shown on the Contract drawings.

C. Electrical Work: Electrical motor driven equipment specified herein shall be provided complete with motors, motor starters, and controls. Motor starters shall be provided complete with properly sized thermal overload protection and other components necessary for the motor control specified. Manual or automatic control and protective devices shall be provided as required for the operation herein specified and any control wiring required for controls and devices but not indicated.

D. Corrosion Prevention: Unless specified otherwise, equipment fabricated from ferrous metals that do not have a zinc (hot-dip) coating shall have a coating conforming to ASTM A 123 with baked finish coat of polyester, epoxy polyester, or epoxy. The factory coating shall be capable of withstanding a salt-spray fog test, 125 hours indoors and 500 hours for equipment located outdoors. The salt spray fog test shall be in accordance with ASTM B 117 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 creepage beyond 3 mm on either side of the scratch mark. The film thickness of the factory coating or paint system applied on the equipment shall be not less than film thickness used on the test specimen.

E. Safety Standards:

1. The design, manufacture, and installation of mechanical refrigeration equipment shall be in accordance with ASHRAE 15.

2. Drive mechanism and other moving parts shall be fully guarded in accordance with ANSI B 15.1. Guards shall be fabricated from steel and expanded metal, rigidly mounted and readily removed without disassembly.

2.2 MINI-SPLIT AIR CONDITIONERS

A General:

1. Mini split air conditioners shall consist of indoor evaporator blower unit and outdoor remote air cooled condensing unit.

2. The two units shall be designed to be used together and ratings shall be based on the use of the matched assemblies.

3. The mini units shall be designed, constructed and rated in accordance with ARI Standards.

4. Performance diagrams shall be provided for units with capacities not certified by ARI to demonstrate that the components of the air conditioning system furnished will satisfy requirement specified or indicated on the Contract Drawings.

5. Each unit shall be provided with a factory operating charge of refrigerant a holding charge. Refrigerant gas shall be R134a. │

6. Where units are shipped with refrigerant holdings charge, the system shall be completely charged in the field.

7. The outdoor and indoor units shall conform to the requirements of ARI 210

and UL 465.


1. Energy Efficiency Ratio (EER=11.5): Data shall be submitted to demonstrate that the units will produce the efficiency rates specified.

B. Evaporator – Blower Unit (Indoor Unit):

1. The evaporator – blower unit shall include; cooling coil, electric heating coil, expansion device, blower, 25 mm cleanable air filter, condensate pan, drain and controls. The exposed type unit shall have enameled finish casing.

2. Blower shall be quiet conforming to AMCA 210, specifically designed to be suitable for the opening pressure and shall have either grease able or permanently lubricated ball or roller bearings.

3. Fans assemblies shall be statically and dynamically balanced in the fan housing and final assembly.

4. Fan motors shall conform to NEMA MG2. Motor starter shall conform to NEMA ICS 1, and shall be magnetic across-the line type with weather-resistance enclosed. Motor shall be totally enclosed type.

5. Motor starters shall be magnetic across-the-line with weather resistance enclosure.

C. Condensing Unit (Outdoor Unit):

The condensing unit shall be a complete package, factory assembled electrically operated unit, consisting of weatherproof housing and vibration mounting hermetic type compressor, air-cooled condenser, condenser fan and motor, and the necessary structure frame, valves, piping, wiring and control. Condenser coils shall be of copper fins and copper tubes.

2.3 FILTERS

1. Filters to filter fresh air and return air shall be located as indicated inside air conditioners, inside filter box, inside combination air-filter mixing box. Filters shall be replaceable throwaway type. Filters shall conform to UL 900.

2. Filters shall conform to ASHRAE Standards 52.1 and shall be throwaway frames and media, permanent frames and replaceable media type, 50 mm thick, Grade B, high dust holding capacity. Holding frames shall be fabricated from not less than 1.5 mm galvanized steel. Each holding frame shall be equipped with suitable cell holding devices, and gasket cell


seats. Where indicated or required, filter bank shall be erected, and all joints shall be airtight.

3. All air filters shall have a minimum atmospheric dust spot efficiency of 30 percent based upon ASHRAE standards.

4. Inclined-type manometers shall be provided for filter stations of 3,400 m 3/h capacity or larger including filters furnished as integral parts of air handling units and filters installed separately. Manometers shall be of sufficient length to read at least 2.5 m of water gauge, shall be graduated in 2.5 mm and equipped with spirit level. Each manometer shall be equipped with over- pressure safety traps to prevent loss of oil, and two three-way vent valves for checking zero setting.

2.4 REFRIGERANT PIPING AND ACCESSORIES

1. General:

a. Material and dimensional requirements for piping, fittings, valves and accessories shall conform to ANSI B 9.1 and B 31.5 except as herein specified.

b. Piping, fittings, valves and accessories shall be delivered to Work Site cleaned, dehydrated and sealed.

2. Field Assembled Piping:

a. Piping shall be seamless copper hand drawn tubing conforming to ASTM B 42 Type K.

b. Soft annealed copper tubing conforming to ASTM B 280 may be used where flare connections are required in nominal sizes less than 25 mm only.

3. Fittings:

a. Fittings for copper tubing shall conform to ANSI B 16.22

b. Bronze flanges shall conform to ANSI B 16.21.

c. Refrigerant flared tube fittings shall conform to ANSI B 70.1.

4. Refrigeration Valves:

Valves shall be designed, manufactured, and tested specifically for the service in all respects including materials. Internal parts shall be removable for inspection


or replacement without the necessity of applying heat or breaking pipe connections. Direction of flow shall be legibly and permanently indicated on the valve body.

a. Globe and Angle Refrigerant Valves: Valves shall be forged brass or bronze alloy with packed stem and seal cap. Packless type valves with hand wheels and forged brass or bronze alloy bodies with brazing ends may be used in sizes up to and including 22 mm. Bonnets shall be replaceable with the valve in place. All refrigerant valves shall be back-seating type to allow repacking under pressure.

b. Check Valves: Valves shall be swing or lift type, designed for low pressure drop. Body shall be forged brass or bronze alloy with brazing ends. Valves shall be tight closing and silent operating.

c. Relief Valves, Safety, Refrigerant: Valves shall have bodies of forged brass or bronze and nonferrous corrosion resistant internal working parts. Valves shall have either female threaded or brazing connections.

d. Valves shall be installed on refrigeration systems and set in accordance with ANSI B 9.1. Manufacturer's published air discharge capacity ratings of relief valves shall be submitted.

e. Solenoid Valves, Refrigerant: Valves shall be of the two-position, direct acting or pilot operated types, opened or closed electrically as specified for use with liquid or gas. Valves shall conform to ARI 760. Valves shall be designed for the pressure drop required and as listed by ARI 760 for the service. Valves shall have seal capped manual opening stems and shall be constructed so that they may be serviced without removing from the line. Each valve shall include a coil housing, stem and plunger or piston assembly nonmagnetic to the plug, stainless steel enclosing tube, seat and plunger, and inlet and outlet indications on the body. Manufacturer's published ratings and maximum operating pressure differential shall be submitted. The coil housing shall include a moisture-proof coil in a metal housing with electrical wires extending through a female pipe tap conduit connection. Coils shall be wired for the electrical current used and be capable of withstanding the temperature of the liquid or gas encountered plus the heat from the coil for the longest running time expected. Bodies, stems and pistons shall be of a material that will not corrode or pit when used in the refrigerant systems. Threads on valves with threaded connections shall conform to American Standard National Pipe Thread (NPT) in accordance with ANSI B 2.1 or B 2.2. Pilot operated valves with floating piston shall be used on 12.5 mm or larger port size valves. Valves in sizes 32 mm and larger shall have tongue and grooved flange connections with companion flanges brazed to piping. Sizes 5 mm


and smaller may either have female thread connections or the valve may be nonferrous with brazing connections.

5. Strainers shall be single type with brass bodies. Direction of flow shall be permanently indicated on the body. The screen cover shall be flanged and bolted for pipe sizes 25 mm and larger and for smaller sizes the cover may be flanged and bolted or screwed. The body shall be constructed to provide adequate storage area for foreign material without excessive pressure drop. Free area of the screen shall be not less than 5 times the area of the strainer inlet pipe. Screen mesh size shall be not less than 80 for liquid refrigerant lines of 25 mm in diameter and not less than 60 for line sizes over 25 mm in diameter. Screen mesh sizes shall be not more than 40 for refrigerant suction lines. Strainer screens shall be reinforced with 8 or 10 wire mesh screen. Brazed strainer and screen joints shall be brazed with silver solder.

6. Refrigerant dryers shall be solid desiccant type. Water capacity flow rate capacity within the specified pressure drop, and safety shall conform to ARI 710. Dryers 820 ml and larger shall be the cartridge refillable type, and provided with a valve bypass of the same size as the liquid line. Drier body shall be of brass or steel and have means for holding the desiccant securely in place and distributing the liquid refrigerant evenly throughout the desiccant. Dryers may be of the combination drier-indicator type.

7. Moisture indicators in the liquid line of refrigerant systems shall contain indicating material that will indicate, by varying degrees of color change, based on 38 degrees K, a moisture content in the range of 10 to 30 ppm in R12; 25 to 90 ppm in R502, and 45 to 180 ppm in R22. Indicators shall be a brass or bronze or heavily copper plated steel fitting, with the indicator material located under a bullseye. Indicators shall be capable of withstanding a test pressure of 2400 kPa without damage.

8. Sight glasses shall be of nonferrous material, unless combined as a part of the moisture indicator. Cover caps shall be provided. Sight glass indicators shall be capable of withstanding a test pressure of 2400 kPa without damage. Sight glass body shall be forged brass or bronze with fittings as specified for the piping.

9. Provide pipe sleeves for all pipes and tubing, which penetrate the building structure. Sleeves shall be securely retained in position and location before and during construction. Space between pipe and sleeves, or between insulation of pipe and sleeves, shall be not less than 6 mm between outside of pipe or insulation, and inside wall of sleeves. Pack the annular space with hemp or fiber glass, and seal with elastic cement. Sleeves for uninsulated pipes shall have ends flush with finished wall surfaces and the pipe or tubing shall be provided as above, with outside perimeter of pipe calked to the sleeve. Extend sleeves for insulated pipes 13 mm from the wall faces insulation with mastic. Extend sleeves for lines passing through floors 8 cm above finished floor slab, and calk to the


slab. Provide lines passing through roof areas with necessary flashing and counter flashing to provide a water-tight roof seal.

10. Pipe sleeves in equipment room walls, floors, and roof shall be as specified under section entitled, "Vibration Isolation of Equipment".

PART 3 - EXECUTION

3.1 INSPECTION

A. The Contractor shall inspect all products for damage immediately before installation. Any products that are damaged or not in accordance with the Specifications shall immediately be repaired or removed from the site and replaced.

3.2 INSTALLATION

A. General:

1. The air conditioning system shall be installed in strict accordance with the manufacturer's recommendations and in accordance with all applicable codes and standards listed in para. 1.2.

2. The air conditioning system shall be installed as shown on the Contract drawings and on the approved shop drawings.

B. Equipment:

1. Equipment shall be installed strictly in accordance with the manufacturer’s recommendations and Section 15050, paragraph 3.10 "Equipment Installation".

2. Room air conditioners shall be pitched to ensure condensate drain to drain pan without overflow.

C. Vibration Isolation:

1. Vibration isolation for piping and equipment shall be in accordance with Section 15050, paragraph 3.2 “Vibration Control”.

2. Room air conditioners shall be installed in such a manner that no vibration is transmitted through the building structure.

D. Refrigerant Piping and Accessories:


1. Refrigeration piping and accessories shall be installed in accordance with ANSI B 9.1 and B 31.5.

2. Provisions shall be made to automatically return oil on halocarbon systems.

3. Return Oil from Refrigerant System: Refrigerant lines shall be installed so that the gas velocity in the evaporator suction line is sufficient to move the oil along with the gas to the compressor. Where equipment location requires vertical risers, the line shall be at minimum system loading and corresponding reduction of gas volume. A double riser shall be installed when excess velocity and pressure drop would result from full system loading. The larger riser shall have a trap, of minimum volume, obtained by use of 90° and 45° elbows. The small riser shall be arranged with inlet close to bottom of horizontal line. Valves shall not be installed in risers.

4. Refrigerant dryers, sight glass liquid indicators, moisture indicators, and strainers shall be installed in refrigerant piping for remote installations when not furnished by the manufacturer as part of the equipment. Dryers shall be installed in liquid line with service valves and valves bypass line, which are the same size as liquid line in which the driver is installed. Size of dryers shall be determined by the piping and installation of the unit on location. Dryers of 820 ml and larger shall be installed vertically with the cover for removing cartridge at the bottom.

5. Moisture indicators shall be installed in the liquid line downstream of the drier. Indicator connections shall be the same size as the liquid line in which it is installed.

6. Strainers shall be located close to the equipment they are to protect. A strainer shall be installed in the common refrigerant liquid supply to two or more thermal valves in parallel when each thermal valve has a built-in strainer. Strainers shall be installed with screen down and in direction of flow as indicated on strainer's body.

7. Solenoid valves shall be installed in horizontal lines with stem vertical and with flow in direction indicated on the valve. If not incorporated as integral part of the valve, strainers shall be installed upstream of the solenoid valve. Service valves shall be installed upstream of the solenoid valve, upstream of the strainer, and downstream of the solenoid valve. The internal parts of the solenoid valve shall be removed when brazing the valve.

E. Auxiliary drain pans shall be installed under all drain pans of units located above finished ceilings or over mechanical or electrical equipment where condensate overflow over unit drain may cause damage to ceilings, piping, and equipment


below. Drain lines shall be installed for all drain and auxiliary drain pans. The drain shall be trapped from bottom pan of air-conditioning units to ensure complete pan drainage. Drain lines shall be full size of opening.

F. Air filters shall be installed so that access space for servicing the filters is provided. Filters shall be installed with suitable sealing to prevent bypassing of air.

G. Inspection plates and test holes where required in casings for air balance measurements shall conform to SMACNA Low Velocity Duct Construction Standards. Test holes shall be a factory-fabricated, airtight, non-corrosive and with screw cap and gasket. Cap shall be extended through insulation.

3.3 FIELD TESTS AND INSPECTIONS

A. All tests shall be performed and materials and equipment required for tests shall be furnished by the Contractor. Equipment and material certified as having been successfully tested by the manufacturer in accordance with referenced specifications and standards will not require retesting before installation. Equipment and materials not tested at the place of manufacturer shall be tested before or after installation, as applicable, where necessary to determine compliance with referenced codes and standards.

B. Upon completion of installation of the air conditioning equipment, all factory and field refrigerant piping shall be tested with an electronic-type leak detector to acquire a leak tight refrigerant system. If leaks are detected at the time of installation or during the Warranty period, the entire refrigerant charge shall be removed from the system, the leaks repaired and the system rested.

C. After system is found to be without leaks, the system shall be evacuated using a reliable gauge and a vacuum pump capable of pulling a vacuum of at least 1 mm Hg absolute. The system shall be evacuated in strict accordance with the triple-evacuation and blotter method or in strict accordance with equipment manufacturer's printed instructions. System leak testing, evacuation, dehydration, and charging with refrigerant shall conform with ARI 260.

D. The air conditioning system and its components shall be started and initially placed under operation and checked to see that it is functioning correctly. Safety and automatic control instruments shall be adjusted as necessary to place them in proper operation and sequence. The operational test shall be not less than eight hours.

E. Upon completion of evacuation, charging, start-up, final leak testing, and proper adjustment of controls, the system shall be performance tested to demonstrate that it complies with the performance and capacity requirements of the Specifications and Contract drawings. If performance test cannot be


performed/completed for seasonal reasons, lack of occupancy or for other reasons, the test may need to be deferred. Normally, cooling performance test shall be done during summer. The system shall be tested for not less than eight hours, during which time hourly readings shall be recorded. At the end of the test period, the readings shall be averaged and the average shall be considered to be the system performance. The following readings shall be taken:

1. Refrigerant compressor suction and discharge pressures.

2. Voltage and current each motor.

3. Air quantities

4. Cooling coil entering and leaving air temperatures

5. Ambient temperatures

F. Sound pressure level measurements shall be conducted on each unit. Sound power levels shall be calculated by ASHRAE Systems Handbook. Test results and calculations shall be submitted to the Royal Commission.

3.4 TESTING AND BALANCING

A. The unitary air conditioning systems shall be tested and balanced in accordance with Section 15040, "Systems Adjusting, Testing and Balancing".

+ + END OF SECTION 15652 + +


Section 15652

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