HVAC15651- GENERAL: A) Each room designed to be living space will have a minimum of one duct and vent except where the size of the room would require more than one. Ducting requirements will be calculated using industry standard duct calculations based on the heat and cooling load required by each room. The exception to this would be in bathrooms where there is electric heat and an electric ventilation fan. The return air grill and thermostat will be placed within the structure in a manner that will allow good air circulation and high performance of the heating and cooling cycle. Contractor will insure system balance by the practice of undercutting doors, installing door grills, or installing jumper ducts. B) The air conditioning will perform to maintain a 20 degree temperature drop, measured at the vent closest to the evaporator, from the outside temperature or a maximum of 85 degrees, whichever is warmer. There should not be an excess of 5 degrees in temperature variation measured at the vent furthest from the evaporator. Heating equipment should be able to maintain a minimum of 68 degrees in each room intended as living space. C) All installations of HVAC equipment must meet the requirements for natural and mechanical ventilation requiring 2 complete air changes per hour with one fifth of the air being outside air. In unusually tight houses, a make-up air duct is required. Contractor to include gas riser and or electrical circuitry, work area and walkway (minimum 5/8 at 24 o.c. floor/ ceiling joints) from the access entrance to the unit. D) All cutting of floors, walls, ceilings and partitions will be kept to a minimum not to exceed De minimis levels and subsequent repair work of blocking and re-inserting cut piece will be performed by the Contractor. All debris and abandoned HVAC equipment will be removed and disposed of by the Contractor. Contractor at no time will cut, drill or notch any supporting framing members without consulting the Housing Inspector. 15660- CONDENSING UNIT: A) Unit will have a 14 SEER rating or better stamped on the condensing unit and will be AHRI Certified Product Performance matched to interior unit. B) There will be an electrical service disconnect within arm's reach of the unit but not behind the condenser or condenser cage and the wiring must be placed in a water tight flexible conduit with water tight connections. C) The condensing unit will be free of obstructing vegetation and walls with a minimum of 10 and a maximum of 24 clearance from the nearest wall, 18 on the side of the service panel, and 10 clearance on the remaining sides. If the unit is installed under an awning, there must be 36" clearance from the top to allow for heat distribution and a method of deflection from under the awning. D) The condensing unit must be placed on an approved poured concrete pad and will be bolted from within to the pad base and must be level. E) Compressor shall have a painted metal cage with bars welded vertically 4 apart or of heavy wire mesh. The cage will be lockable and be hinged to lift away from the compressor to allow total access for repairs and or replacement. The cage will be attached to the concrete pad or into the ground and secured with concrete. Heavy duty keyed lock will be provided. F) The suction/vapor line will be insulated with 3/4" Armflex or equivalent pipe insulation and the 24 volt thermostat line will be attached to the vapor line by means of zip ties. The 24 volt wire must enter the condensing unit through a rubber grommet. Low voltage wire must be installed in a conduit. G) There will be a liquid line dryer installed either within the condensing unit or externally on the liquid line. H) The Contractor will install pull-down attic stair where required. Stair will be placed conveniently to the equipment in the attic. There will be sufficient clearance for the stairs to pull down as well as clearance to gain access above. Rough opening for stair unit will be framed on all sides with 2x6 nominal thickness lumber and secured with screws. Stair opening will be large enough to accommodate the equipment. Weather stripping is to be applied to the opening to seal the door from attic air filtration. Attic stairs must have a minimum load rating of 300 pounds. Telescopic ladders can be substituted at the approval of the Housing Inspector. 15661- REFRIGERANT LINES: A) Refrigerant tubing will be refrigerant grade, dehydrated and sealed copper tubing of a length and diameter recommended by the manufacturer. B) Refrigerant lines will be brazed with a silver alloy material at all connections including those to the condensing unit and the evaporator. Flared connections will not be authorized due to refrigerant loss from vibration. C) Suction line will be insulated fully from the condensing unit to the evaporator using un-split lengths of 3/8 pipe insulation material. All joints in the insulation will be taped fully. D) Any holes cut in the soffit or wall of the structure for passage of wires or tubing must be sealed with a silicon caulk. E) Wherever possible, the refrigerant lines and thermostat wiring will be run within the wall or through the crawl space. As a last resort, the lines and thermostat wiring must be encased in a sheet metal chase from where the lines meet the wall horizontally up to where the lines enter the soffit. F) Exterior refrigerant accesses ports shall be fitted with locking-type tamper resistant port caps. 15662- EVAPORATOR/COOLING COIL: A) Evaporator will be of such size and capacity to accommodate the needs of the condensing unit and should be of a make that fits proportionately to the furnace/blower unit. B) Contractor is to assure that the appropriate sized orifice or expansion device is in place. C) Evaporator should be affixed to the blower unit with hex head sheet metal screws and sealed with UL-181 metal duct tape and approved mastick to include the openings for the refrigerant lines and the drain line. D) A manufactured insulated sheet metal transition is to be used when the evaporator is not proportionate to the blower unit. E) Condensation waste lines will be of " PVC and must be in accordance with applicable codes, i.e. draining into a wet drain to prevent gasses from entering into the climate control system. Examples of an acceptable drain would be the washer drain or the tub overflow. F) When the unit is installed vertically in a closet with no possible way to send condensate waste to an approved drain, the Plumbing Inspector can authorize draining to the outside. Plumbing Inspector will specify where the drain will be placed. Note: In attic installations, a secondary drain pan is required to accommodate the full size of the blower unit and evaporator unit. The secondary drain line is to be in accordance with applicable codes. The secondary drain must not flow onto, near the condensing unit, or over any door. The Housing Inspector and Homeowner will specify where to place the secondary drain i.e. by the living room or kitchen window, or over the tub. 15761- GAS WALL FURNACE, 35-50K BTU: When specified in DOS, Contractor to install 35,000 or 50,000 BTU or larger gas wall furnace. Work will include removal of the old unit, installation of a WALL HEATER, manufactured by Cozy Furnace Company or equal, all necessary gas pipe, flex lines, gas stopcocks and connections to meet plumbing code, double-wall vent pi
