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DocuSign Envelope ID: B94F2D40-3B3C-47A7-86C2-6F1 B4F92C62C <br /> Orange County Emergency Services Building Construction Documents <br /> C. Electrical <br /> 1. Unit shall be provided with factory installed and factory wired, non-fused disconnect switch. <br /> 2. Unit shall be provided with a factory installed and factory wired 115V, 12 amp GFI outlet <br /> disconnect switch in the unit control panel. <br /> 3. Unit shall be provided with phase and brown out protection which shuts down all motors in the <br /> unit if the electrical phases are more than 10% out of balance on voltage, the voltage is more <br /> than 10% under design voltage or on phase reversal. <br /> D. Supply Fans <br /> 1. Unit shall include direct drive, unhoused, backward curved, plenum supply fans. <br /> 2. Blowers and motors shall be dynamically balance and mounted on rubber isolators. <br /> 3. Motors shall be premium efficiency ODP with ball bearings rated for 200,000 hours service <br /> with external lubrication points. <br /> 4. Variable frequency drives shall be factory wired and mounted in the unit. Fan motors shall be <br /> premium efficiency. <br /> E. Exhaust Fans <br /> 1. Exhaust dampers shall be sized for 100% relief. <br /> 2. Fans and motors shall be dynamically balanced. <br /> 3. Motors shall be premium efficiency ODP with ball bearings rated for 200,000 hours service <br /> with external lubrication points. <br /> 4. Access to exhaust fans shall be through double wall, hinged access doors with quarter turn <br /> lockable handles. <br /> 5. Unit shall include belt driven, unhoused, backward curved, plenum exhaust fans. <br /> 6. Variable frequency drives shall be factory wired and mounted in the unit. Fan motors shall be <br /> premium efficiency. <br /> F. Cooling Coils <br /> 1. Evaporator Coils <br /> a. Coils shall be designed for use with R-410A refrigerant and constructed of copper tubes <br /> with aluminum fins mechanically bonded to the tubes and galvanized steel end casings. <br /> Fin design shall be sine wave rippled. <br /> b. Coils shall have interlaced circuitry and shall be standard capacity. <br /> c. Coils shall have interlaced circuitry and shall be minimum 6 row high capacity. <br /> d. Coils shall be hydrogen or helium leak tested. <br /> e. Coils shall be furnished with factory installed expansion valves. <br /> G. Refrigeration System <br /> 1. Unit shall be factory charged with R-410A refrigerant. <br /> 2. Compressors shall be scroll type with thermal overload protection and carry a 5 year <br /> non-prorated warranty, from the date of original equipment shipment from the factory. <br /> 3. Compressors shall be mounted in an isolated service compartment which can be accessed <br /> without affecting unit operation. Lockable hinged compressor access doors shall be fabricated <br /> of double wall, rigid polyurethane foam injected panels to prevent the transmission of noise <br /> outside the cabinet. <br /> 4. Compressors shall be isolated from the base pan with the compressor manufacturer's <br /> recommended rubber vibration isolators, to reduce any transmission of noise from the <br /> compressors into the building area. <br /> 5. Each refrigeration circuit shall be equipped with expansion valve type refrigerant flow control. <br /> 6. Each refrigeration circuit shall be equipped with automatic reset low pressure and manual <br /> reset high pressure refrigerant safety controls, Schrader type service fittings on both the high <br /> pressure and low pressure sides and a factory installed replaceable core liquid line filter <br /> driers. <br /> 7. Unit shall include a variable capacity scroll compressor on the lead refrigeration circuit which <br /> shall be capable of modulation from 10-100% of its capacity. <br /> 8. Lead refrigeration circuit shall be provided with hot gas reheat coil, modulating valves, <br /> electronic controller, supply air temperature sensor and a control signal terminal which allow <br /> the unit to have a dehumidification mode of operation, which includes supply air temperature <br /> control to prevent supply air temperature swings and overcooling of the space. <br /> PDC Project 18102 100 PERCENT OUTSIDE AIR 23 74 00- 3 <br /> 12/17/2018 PACKAGED DX UNIT <br />