Carrier SINGLE PACKAGE ROOFTOP 48HC Installation Instructions Manual

Also see for 48TC*D: Service and maintenance instructions Installation instructions

18Factory--Option Thru--Base Connections —Electrical Connections: Knockouts are located in thecontrol box area. Remove the appropriate size knockoutfor high voltage connection. Use the field suppliedconnector depending on wiring or conduit being utilized.Remove the 7 / 8 --in (22mm) knockout and appropriateconnector for low voltage wiring. If non--unit poweredconvenience outlet is being utilized, remove the 7 / 8 --in(22mm) knockout and utilize appropriate connector for115 volt line. See “Step 12 — Making ElectricalConnections” for details.Gas Connections: Remove the knockout in the base panand route 3 / 4 --in. gas line up through the opening. Installan elbow and route gas line through opening in panel afterfirst removing plastic bushing. Install a gas shut offfollowed by a drip leg and ground--joint union. Route gasline into gas section through the grommet (Part #:KA56SL112) at the gas inlet and into the gas valve. SeeFig. 17 and Table 2. If a regulator is installed, it must belocated 4 feet (1.22 meters) from the flue outlet.Some municipal codes require that the manual shutoffvalve be located upstream of the sediment trap. SeeFig. 18 for typical piping arrangements for gas piping thathas been routed through the sidewall of the base pan.When installing the gas supply line, observe local codespertaining to gas pipe installations. Refer to the NFPA54/ANSI Z223.1 NFGC latest edition (in Canada, CAN/CSAB149.1). In the absence of local building codes, adhere tothe following pertinent recommendations:1. Avoid low spots in long runs of pipe. Grade all pipe1 / 4 --in. in every 15 ft (7 mm in every 5 m) to preventtraps. Grade all horizontal runs downward to risers.Use risers to connect to heating section and to meter.2. Protect all segments of piping system against physicaland thermal damage. Support all piping with appro-priate straps, hangers, etc. Use a minimum of onehanger every 6 ft (1.8 m). For pipe sizes larger than1 / 2 --in., follow recommendations of national codes.3. Apply joint compound (pipe dope) sparingly and only tomale threads of joint when making pipe connections.Use only pipe dope that is resistant to action of lique-fied petroleum gases as specified by local and/or nation-al codes. If using PTFE (Teflon) tape, ensure the materi-al is Double Density type and is labeled for use on gaslines. Apply tape per manufacturer’s instructions.4. Pressure--test all gas piping in accordance with localand national plumbing and gas codes before connect-ing piping to unit.NOTE: Pressure test the gas supply system after the gassupply piping is connected to the gas valve. The supplypiping must be disconnected from the gas valve during thetesting of the piping systems when test pressure is inexcess of 0.5 psig (3450 Pa). Pressure test the gas supplypiping system at pressures equal to or less than 0.5 psig(3450 Pa). The unit heating section must be isolated fromthe gas piping system by closing the external main manualshutoff valve and slightly opening the ground--joint union.Check for gas leaks at the field--installed andfactory--installed gas lines after all piping connections havebeen completed. Use soap--and--water solution (or methodspecified by local codes and/or regulations).FIRE OR EXPLOSION HAZARDFailure to follow this warning could result in personalinjury, death and/or property damage.S Connect gas pipe to unit using a backup wrench toavoid damaging gas controls.S Never purge a gas line into a combustion chamber.S Never test for gas leaks with an open flame. Use acommercially available soap solution madespecifically for the detection of leaks to check allconnections.S Use proper length of pipe to avoid stress on gascontrol manifold.! WARNINGNOTE: If orifice hole appears damaged or it is suspected tohave been redrilled, check orifice hole with a numbered drillbit of correct size. Never redrill an orifice. A burr--free andsquarely aligned orifice hole is essential for proper flamecharacteristics.BURNERORIFICEA93059Fig. 20 -- Orifice Hole48HC