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s � <br /> Guide Specification for Page: 15 <br /> MYORK Prestige <br /> 9. Electrical Connections <br /> a. All unit power wiring shall enter unit cabinet at a single,factory-prepared, knockout location. <br /> b. Thru-the-base capability. <br /> (1.) Standard unit shall have a thru-the-base electrical location(s)using a raised,embossed portion of the unit <br /> basepan. <br /> (2.) Optional,factory-approved,water-tight connection method must be used for thru-the-base electrical <br /> connections. <br /> (3.) No basepan penetration, other than those authorized by the manufacturer, is permitted. <br /> 10. Component access panels(standard) <br /> a. Cabinet panels shall be easily removable for servicing. <br /> b. Unit shall have one factory installed,toolless, removable,filter access panel. <br /> c. Panels covering control box, indoor fan, indoor fan motor,gas components(where applicable), and compressors <br /> shall have a molded composite handles. <br /> d. Handles shall be UV modified, composite.They shall be permanently attached, and recessed into the panel. <br /> e. Screws on the vertical portion of all removable access panel shall engage into heat resistant, molded composite <br /> collars. <br /> f. Collars shall be removable and easily replaceable using manufacturer recommended parts. <br /> 23 81 19. 13.1 Gas Heat <br /> 1. General <br /> a. Heat exchanger shall bean induced draft design. Positive pressure heat exchanger designs shall not be allowed. <br /> b. Shall incorporate a direct-spark ignition system and redundant main gas valve. <br /> c. Gas supply pressure at the inlet to the rooftop unit gas valve must match that required by the manufacturer. <br /> 2. The heat exchanger shall be controlled by an integrated gas controller(IGC)microprocessor. <br /> a. IGC board shall notify users of fault using an LED(light-emitting diode). <br /> b. The LED shall be visible without removing the control box access panel. <br /> c. IGC board shall contain algorithms that modify evaporator-fan operation to prevent future cycling on high <br /> temperature limit switch. <br /> d. Unit shall be equipped with anti-cycle protection with one short cycle on unit flame rollout switch or 4 continuous <br /> short cycles on the high temperature limit switch. Fault indication shall be made using an LED. <br /> 3. Standard Heat Exchanger construction <br /> a. Heat exchanger shall be of the tubular-section type constructed of a minimum of 20-gauge steel coated with a <br /> nominal 1.2 mil aluminum-silicone alloy for corrosion resistance. <br /> b. Burners shall be of the in-shot type constructed of aluminum-coated steel. <br /> c. Burners shall incorporate orifices for rated heat output up to 2000 ft(610m)elevation.Additional accessory kits <br /> may be required for applications above 2000 ft(610m)elevation,depending on local gas supply conditions. <br /> d. Each heat exchanger tube shall contain multiple dimples for increased heating effectiveness. <br /> 6. Induced draft combustion motor and blower <br /> a. Shall be a direct-drive, single inlet,forward-curved centrifugal type. <br /> b. Shall be made from steel with a corrosion-resistant finish. <br /> c. Shall have permanently lubricated sealed bearings. <br /> d. Shall have inherent thermal overload protection. <br /> e. Shall have an automatic reset feature. <br /> 23 81 19. 13.J Coils <br /> 1. Standard Aluminum Fin/Copper Tube Coils <br /> a. Standard evaporator and condenser coils shall have aluminum lanced plate fins mechanically bonded to seamless <br /> internally grooved copper tubes with all joints brazed. <br /> b. Evaporator coils shall be leak tested to 150 psig, pressure tested to 450 psig, and qualified to UL 1995 burst test at <br /> 1775 psig. <br /> c. Condenser coils shall be leak tested to 150 psig, pressure tested to 650 psig, and qualified to UL 1995 burst test at <br /> 1980 psig. <br />