VA 23 81 23-2011 COMPUTER-ROOM AIR-CONDITIONERS.pdf

1、04-11 23 81 23 - 1 SECTION 23 81 23 COMPUTER-ROOM AIR-CONDITIONERS SPEC WRITER NOTES: 1. Delete between /-/ if not applicable to project. Also delete any other item or paragraph not applicable in the section and renumber the paragraphs. 2. The spec writer shall review the Physical Security Design Ma

2、nual for VA Facilities to determine and include any Mission Critical or Life Safety requirements called out. PART 1 - GENERAL 1.1 DESCRIPTION A. This section specifies process cooling split systems air conditioning unit. B. Definitions: 1. Energy Efficiency Ratio (EER): A ratio calculated by dividin

3、g the cooling capacity in Btuh by the power input in watts at any given set of rating conditions, expressed in Watts (Btu/h) per watt. 2. Coefficient of Performance (COP): A ratio calculated by dividing the change in heating or cooling capacity (Btu/h) to the energy consumed by the system (kW), expr

4、essed in Btu/kWh. 3. Unitary (AHRI): 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. 4. CRAC Units: Computer Room Air Conditioning Units. 1.2 RELATED WORK A. Section 01

5、00 00, GENERAL REQUIREMENTS: Requirements for pre-test of equipment. /B. Section 13 05 41, SEISMIC RESTRAINT REQUIREMENTS FOR NON-STRUCTURAL COMPONENTS: Seismic requirements for non-structural equipment./ C. Section 23 05 11, COMMON WORK RESULTS FOR HVAC: General mechanical requirements and items, w

6、hich are common to more than one section of Division 23. D. Section 23 21 23, HYDRONIC PUMPS and Section 23 22 23, STEAM CONDENSATE PUMPS: Requirements for pumping equipment. E. Section 23 05 41, NOISE and VIBRATION CONTROL FOR HVAC PIPING and EQUIPMENT: Requirements for vibration isolators and room

7、 noise level. F. Section 23 07 11, HVAC, PLUMBING, and BOILER PLANT INSULATION: Requirements and for ducts and piping insulation. G. Section 23 23 00, REFRIGERANT PIPING: Requirements for field refrigerant piping. Provided by IHSNot for ResaleNo reproduction or networking permitted without license f

8、rom IHS-,-,-04-11 23 81 23 - 2 H. Section 23 21 13, HYDRONIC PIPING and Section 23 22 13, STEAM and CONDENSATE HEATING PIPING: Requirements for condensate piping and fittings / and steam piping /. I. Section 23 31 00, HVAC DUCTS and CASINGS: Requirements for sheet metal ducts and fittings. J. Sectio

9、n 23 40 00, HVAC AIR CLEANING DEVICES: Requirements for filters including efficiency. K. Section 23 09 23, DIRECT-DIGITAL CONTROL SYSTEM FOR HVAC: Requirements for controls and instrumentation. L. Section 23 05 93: TESTING, ADJUSTING, and BALANCING FOR HVAC: Requirements for testing, adjusting and b

10、alancing of HVAC system. M. Section 23 08 00 COMMISSIONING OF HVAC SYSTEMS: Requirements for commissioning, systems readiness checklists, and training. 1.3 QUALITY ASSURANCE Refer to specification Section 23 05 11, COMMON WORK RESULTS FOR HVAC. 1.4 SUBMITTALS A. Submit in accordance with specificati

11、on Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, and SAMPLES. B. Manufacturers Literature and Data, rated capacities (at design indoor and outdoor conditions), EER/COP, operating characteristics, required specialties and accessories. Submit published catalog selection data showing equipment ratings

12、 and compliance with required sensible ratio. 1. Indoor Air Conditioning Unit 2. Glycol Pump Package 3. Dry Cooler 4. Air Cooled Condensing Unit C. Submit detailed equipment assemblies with dimensions, operating weights, required clearances. D. Submit wiring diagrams for power, alarm and controls. E

13、. Certification: Submit, simultaneously with shop drawings, a proof of certification: 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 requirement

14、s of Section 23 08 00 COMMISSIONING OF HVAC SYSTEMS. 1.5 GUARANTEE The unit shall be guaranteed against all mechanical defects in material, parts or workmanship and shall be repaired or replaced at the Contractors expense within the period of one year from final acceptance. Contractor shall adhere t

15、o a four hour service response time to troubles during the guarantee period. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-04-11 23 81 23 - 3 1.6 APPLICABLE PUBLICATIONS A. The publications listed below form a part of this specification to the exte

16、nt referenced. The publications are referenced in the text by the basic designation only. B. Federal Specifications (Fed Spec): 00-A-374C-95 . Air-Conditioners with Remote Condensing Units or Remote Air-cooled and Water-Cooled Condenser Units, Unitary TT-C-490D-93 . Cleaning Methods for Ferrous Surf

17、aces and Pretreatments for Organic Coatings C. Air-Conditioning, Heating and Refrigeration Institute (AHRI) Standards: 210/240-08 . Performance Rating of Unitary Air-Conditioning and Air-Source Heat Pump Equipment 340/360-07 . Performance Rating of Commercial and Industrial Unitary Air Conditioning

18、and Heat Pump Equipment 410-01 . Forced-Circulation Air-Cooling and Air-Heating Coils 460-2005 . Performance Rating of Remote Mechanical-Draft Air-Cooled Refrigerant Condensers 520-04 . Performance Rating of Positive Displacement Condensing Units AHRI-DCPP Directory of Certified Product Performance

19、- Applied Directory of Certified Products D. Air Movement and Control Association (AMCA): 210-07 . Laboratory Methods of Testing Fans for Certified Aerodynamic Performance Rating (ANSI) 410-96 . Recommended Safety Practices for Users and Installers of Industrial and Commercial Fans E. American Socie

20、ty of Heating, Refrigerating, and Air-Conditioning Engineers Inc. (ASHRAE): 15-10 Safety Standard for Refrigeration Systems (ANSI) 90.1-10 Energy Standard for Buildings except Low-Rise Residential Buildings (ANSI Approved; IESNA Co-sponsored) 2008 Handbook HVAC Systems and Equipment 2010 Handbook Re

21、frigeration 52.1-92 Gravimetric and Dust-Spot Procedures for Testing Air-Cleaning Devices used in General Ventilation for Removing Particulate Matter F. American Society of Testing and Materials (ASTM): Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,

22、-04-11 23 81 23 - 4 B117-09 Standard Practice for Operating Salt Spray (Fog) Apparatus G. National Electrical Manufacturers Association (NEMA): MG 1-09 (R2010) Motors and Generators (ANSI) H. National Fire Protection Association (NFPA) Publications: 70-11 National Electrical Code 90A-09 . Standard f

23、or the Installation of Air-Conditioning and Ventilating Systems PART 2 - PRODUCTS SPEC WRITER NOTE: Coordinate the Computer Room Air Conditioning Unit location with the OIT (Office of Information Technology) requirements. For remote location outside the computer room, select the equipment and access

24、ories to account for higher static pressure and possible requirement for a larger fan motor. 2.1 FLOOR-MOUNTED UNITS 28 KW (8 TONS) AND LARGER A. Description: Packaged, factory assembled, prewired, and prepiped; consisting of cabinet, fans, filters, humidifier, and controls. B. Cabinet and Frame: We

25、lded steel, braced for rigidity, and supporting compressors and other mechanical equipment and fittings. C. Doors and Access Panels: Galvanized steel with polyurethane gaskets, hinges, and concealed fastening devices. D. Insulation: Thermally and acoustically insulate cabinet interior with - 25-mm (

26、1-inch) thick 24 kg/m3 (1.5 lb /ft3) high-density mineral fiber duct liner coated on airstream side. E. Finish of Interior Surfaces: Surfaces in contact with the airstream shall comply with requirements in ASHRAE 62.1-2007. F. Finish of Exterior Surfaces: Baked-on, textured vinyl enamel; color / as

27、selected from manufacturers standard colors / to match computer equipment /. G. Floor Stand: Welded tubular steel, _high, with adjustable legs and vibration isolation pads. H. Supply-Air Fan(s): Double-inlet, forward-curved centrifugal / or plenum fans(s)/, statically and dynamically balanced. I. Dr

28、ive: /1. Forward-Curved Centrifugal Fan(s): V-belt, with steel shaft with self-aligning ball bearings and cast-iron or steel sheaves, variable and adjustable-pitch motor sheave, minimum of two matched belts, with drive rated at a minimum of two times the nameplate rating of motor./ Provided by IHSNo

29、t for ResaleNo reproduction or networking permitted without license from IHS-,-,-04-11 23 81 23 - 5 /2. Plenum Fans: Direct-drive, Arrangement 4, variable-speed drive fan(s) with aluminum wheels; with multiple fans, the number of fans shall not exceed four./ J. Compressors: Hermetic scroll; with /oi

30、l strainer, internal motor overload protection,/ resilient suspension system, crankcase heater, manual-reset high-pressure switch, and pump-down low-pressure switch. Compressors shall have multiple stages of cooling as listed on the drawing equipment schedule. K. Refrigeration Circuits: Two; each wi

31、th hot-gas mufflers, thermal-expansion valve with external equalizer, liquid-line solenoid valve, liquid-line filter-dryer, sight glass with moisture indicator, service shutoff valves, charging valves, and charge of refrigerant. L. Refrigerant: / R-407C / R-410A / unless otherwise indicated. M. Refr

32、igerant Evaporator Coil: Alternate-row or split-face-circuit, direct-expansion coil of seamless copper tubes expanded into aluminum fins. 1. Coil assembly shall be mounted over stainless-steel drain pan complying with ASHRAE 62.1-2010 and having a condensate pump unit with integral float switch, pum

33、p-motor assembly, and condensate reservoir. N. Integral, Water-Cooled Refrigerant Condenser: / Shell-and-tube type fabricated and labeled according to ASME Boiler and Pressure Vessel Code, Section VIII./ Coaxial tube-in-tube type. / Condenser shall have liquid-line stop valve and head-pressure-actua

34、ted, / two-way / / three-way / regulating valve. Terminate fluid connections outside cabinet. 1. Cooling Medium: / Water / Glycol solution /. SPEC WRITER NOTE: For high-humidity locations (VA HVAC Design Manual), provide E-coated aluminum fins and corrosion-resistant cabinets. See Paragraph 2.7 belo

35、w O. Remote Air-Cooled Refrigerant Condenser: Corrosion-resistant cabinet, copper-tube /aluminum-fins/ /E-coated aluminum-fins/ coils arranged for two circuits, multiple direct-drive propeller fans with permanently lubricated ball bearings, and single-phase motors with internal overload protection a

36、nd integral electric control panel / and disconnect switch /. Control capacity by / cycling fans / modulating fan speeds / three-way refrigerant bypass with receiver and isolation valve /. P. Hydronic Cooling Coil: Seamless copper tubes expanded into aluminum fins with modulating / two-way / three-w

37、ay / control valve. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-04-11 23 81 23 - 6 1. Control Valve: Class 125 body, with a maximum pressure drop of / 21 kPa (3 psig)/ 35 kPa (5 psig) / at design flow rate. 2. Close-Off (Differential) Pressure Ra

38、ting: 100 percent of pressure differential across valve or 100 percent of total system (pump) head. 3. Mount coil assembly over stainless-steel drain pan complying with ASHRAE 62.1-2010 and having a condensate pump unit with integral float switch, pump-motor assembly, and condensate reservoir. SPEC

39、WRITER NOTE: For high-humidity locations (VA HVAC Design Manual), provide E-coated aluminum fins and corrosion-resistant cabinets. See Paragraph 2.7 below. Q. Remote, Air-Cooled, Propylene Glycol-Solution Cooler: Corrosion-resistant cabinet, copper-tube /aluminum-fin /E-coated aluminum-fin/ coil, mu

40、ltiple direct-drive propeller fans with fan guards, and single-phase motors with internal overload protection and integral electric control panel. Control capacity by cycling fans. 1. Disconnect Switch: Nonautomatic, molded-case circuit breaker with handle accessible when panel is closed and capable

41、 of preventing access until switched to off position. R. Propylene Glycol-Solution Pump Package: Weatherproof and vented enclosure of enameled, galvanized steel on structural base frame containing / one / two / centrifugal pump(s) with mechanical seals; electrical-control cabinet with starters, lead

42、-lag switch, automatic switchover, and alarm light. 1. Piping: Interconnecting piping, to and from remote, air-cooled, glycol-solution cooler, with shutoff valves, flow switches, check valves in pump discharge, unions, and pressurized expansion tank with air purge vent and system-charging connection

43、. SPEC WRITER NOTE: Confirm glycol concentration with actual atmospheric conditions in accordance with the VA HVAC Design Manual. Ensure adequate concentration to allow cold start at winter design temperatures. 2. Glycol: Inhibited propylene glycol and water solution mixed /50:50/_ :_/, suitable for

44、 operating temperature of minus 40 /28/_/ deg C (minus 40/33/_/ deg F). 3. Disconnect Switch: Nonautomatic, molded-case circuit breaker with handle accessible when panel is closed and capable of preventing access until switched to off position. SPEC WRITER NOTE: Choose one of the following coil type

45、s as per project requirements. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-04-11 23 81 23 - 7 S. Heating Coil: SPEC WRITER NOTE: Typically, staged control of electric heat is sufficient for computer room applications. Provide SCR control if more

46、precise control is required. 1. Electric-Resistance Heating Coil: Enclosed finned-tube electric elements arranged for /minimum of three stages/SCR control/, with thermal safety switches, manual-reset overload protection, and branch-circuit over current protection. 2. Refrigerant Heating Coil: Hot-ga

47、s coil of seamless copper tubes expanded into aluminum fins with three-way solenoid valve on first-stage refrigerant circuit. 3. Hot-Water Heating Coil: Seamless copper tubes expanded into aluminum fins with two-way modulating control valve and strainer. a. Control Valve: Class 125 body. b. Maximum

48、Pressure Drop: / 21 kPa (3 psig) / 35 kPa (5 psig) / at design flow rate. c. Close-Off (Differential) Pressure Rating: 100 percent of pressure differential across valve or 100 percent of total system (pump) head. 4. Steam Heating Coil: Seamless copper tubes expanded into aluminum fins with two-way m

49、odulating control valve, strainer, and float-and-thermostatic trap. a. Control Valve: Class 125 body. b. Maximum Pressure Drop (103-kPa (15-psig) Steam): 80 percent of inlet steam pressure. c. Close-Off (Differential) Pressure Rating: 150 percent of operating (inlet) pressure. T. Filter Extended-Surface, Disposable, Panel type