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Orange County West Campus Office Building -HVAC <br />PDC Project 23020 In-Row Computer Room Air Conditioners 23 81 24.01 - 1 <br />SECTION 23 81 24.01 <br />IN-ROW COMPUTER ROOM AIR CONDITIONERS <br />GENERAL <br />1.01 SUMMARY <br />A.These specifications describe requirements for a Thermal Management system.The system shall <br />be designed to control temperature and humidity conditions in rooms containing electronic <br />equipment,with good insulation and vapor barrier.The manufacturer shall design and furnish all <br />equipment to be fully compatible with the heat dissipation requirements of the room. <br />1.02 DESIGN REQUIREMENTS <br />A.The Thermal Management system shall be a Liebert self-contained,factory-assembled unit. <br />Standard 60 Hz units shall be CSA-certified to the harmonized U.S.and Canadian product safety <br />standard,"CSA C22.2 No 236/UL 1995 for Heating and Cooling Equipment"and are marked with <br />the CSA c-us logo. <br />B.The system shall be AHRI Certified™,the trusted mark of performance assurance for heating, <br />ventilation,air conditioning and commercial refrigeration equipment,using AHRI Standard 1360. <br />1.03 SUBMITTALS <br />A.Submittals shall be provided with the proposal and shall include:Single-Line Diagrams; <br />Dimensional,Electrical,and Capacity Data;Piping and Electrical Connection Drawings. <br />PRODUCT <br />2.01 AIR-COOLED REFIGERATION SYSTEM <br />A.Refrigeration System <br />1.The single refrigeration circuit shall include a liquid-line filter drier,a refrigerant sight glass <br />with moisture indicator,an adjustable,externally-equalized expansion valve,and a liquid-line <br />solenoid valve.The indoor evaporator refrigerant piping shall be spun shut with a nitrogen <br />holding charge.Field relief of the Schrader valve shall indicate a leak-free system. <br />B.Hydrophilic-Coated Evaporator Coil <br />1.The direct expansion,tilted-slab cooling coil shall have 7.25 ft2 (0.674 m2 )face area,four or <br />five rows deep.It shall be constructed of copper tubes and hydrophilic-coated aluminum fins. <br />The hydrophilic coating shall significantly improve the speed of condensate drainage from the <br />fins and shall provide superior water carryover resistance.Two stainless steel condensate <br />drain pans shall be provided. <br />C.Compressor <br />1.The compressor shall be scroll-type with variable capacity operation from 20-100%, <br />commonly known as a digital scroll.The compressor solenoid valve shall unload the <br />compressor to provide variable capacity operation.The compressor shall have a suction gas- <br />cooled motor,vibration isolators,internal thermal overloads,manual reset high-pressure <br />switch,rotalock service valves,low-pressure and high-pressure transducer,crankcase <br />heater,internal centrifugal oil pump and an operating speed of 3500 rpm at 60 Hz (2900rpm <br />@ 50 Hz).The compressor shall be located outside the air stream and shall be removable <br />and serviceable from the rear of the unit. <br />2. <br />2.02 CHILLED WATER COOLING SYSTEM <br />2.03 FAN SECTION <br />A.The unit shall be equipped with six plug fans:direct-driven centrifugal fans with backward-curved <br />blades and electronically commutated DC motors;commonly referred to as EC plug fans.The fan <br />speed shall be variable and automatically regulated by the Liebert iCOM through all modes of <br />operation.Each fan shall have a dedicated motor,fault monitoring circuitry and speed controller, <br />which provides a level of redundancy.The impellers shall be made of steel and balanced.The EC <br />plug fans shall be mounted in the front of the unit and draw air through the coil. <br />2.04 ADVANCED AIRFLOW MANAGEMENT <br />Docusign Envelope ID: 8DED1454-68D2-4E36-9FC6-E56FF2124E5D