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NCHFA HOUSING REHABILITATION PROGRAMS -- Energy Standards <br /> 5.0 HVAC Systems. <br /> 5.1 If installation of a new heating and/or cooling system is indicated, the choice of <br /> a system must be based on efficiency of the system and its appropriateness to the <br /> dwelling unit. The keys to efficiency are ratings of systems (HSPF, AFUE, SEER, <br /> etc.), proper sizing (number of BTUs per hour, etc.) and the quality of installation. <br /> New central heating systems must be sized in accordance with ACCA Manual J <br /> specifications and must never exceed the Manual J calculated size. A copy of the <br /> sizing calculations shall be retained in client's case file. <br /> 5.2 All central heating units installed with Program funds must have Annual Fuel <br /> Utilization Efficiency (AFUE) ratings meeting the minimum efficiency levels set by <br /> the National Appliance Energy Conservation Act of 1987. These include: <br /> 1. Ducted Central Heating Equipment . . . . . . . . . . . . . . . . . . . . 789/o AFUE <br /> 2. Mobile-Home Furnaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75% AFUE <br /> 3. Wall Furnaces, < 42,000 Btu/hr input . . . . . . . . . . . . . . . . . . 7357o AFUE <br /> 4. Wall Furnaces, > 42,000 Btu/hr input . . . . . . . . . . . . . . . . . . 74% AFUE <br /> 5. Room Heaters, < 18,000 Btu/hr input . . . . . . . . . . . . . . . . . . 57% AFUE <br /> 6. Room Heaters, 18,000-20,000 Btu/hr input . . . . . . . . . . . . . . . 58% AFUE <br /> 7. Room Heaters, 20,000-27,000 Btu/hr input . . . . . . . . . . . . . . . 63% AFUE <br /> 8. Room Heaters, 27,000-46,000 Btu/hr input . . . . . . . . . . . . . . . 64% AFUE <br /> 9. Room Heaters, > 46,000 Btu/hr input . . . . . . . . . . . . . . . . . . 65% AFUE <br /> All new space/room heaters should be of the direct vented type. <br /> 5.3 Central air conditioners installed with Program funds must have a minimum <br /> SEER (rating) of 9.7 for single package systems or 10.0 for split systems. <br /> 5.4 Heat pumps installed with Program funds must have a minimum HSPF of 6.8 <br /> from Raleigh east or 8.0 west of Raleigh and minimum SEER of 9.7 for single <br /> package systems or 10.0 for split systems. <br /> 5.5 New heat pumps and outside cooling units should be located in areas not <br /> subject to direct sunlight or heat buildup. <br /> 5.6 The delivery system ductwork should be designed in accordance with ACCA <br /> Manual D standards to: 1) avoid "spider system" design by use of a supply <br /> trunk/plenum; 2) size the return air duct for minimum noise; 3) locate intake centrally, <br /> near front door if possible; 4) strap all ductwork as needed to eliminate crimping or <br /> sharp bends in ducts; 5) locate registers at perimeter portions of house; 6) use radius <br /> elbows or turning vanes in all supply trunks with 90 degree turns and not diminish the <br /> 7 <br />