Carrier SINGLE PACKAGE ROOFTOP 48HC Installation Instructions Manual

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

10Step 2 — Plan for Sequence of Unit InstallationThe support method used for this unit will dictate differentsequences for the steps of unit installation. For example, oncurb--mounted units, some accessories must be installed onthe unit before the unit is placed on the curb. Review thefollowing for recommended sequences for installation steps.Curb--mounted installation —Install curbInstall field--fabricated ductwork inside curbInstall thru--base service connection fittings (affectscurb and unit)Rig and place unitRemove top skidInstall outside air hoodInstall smoke detector tubeInstall combustion air hoodInstall flue hoodInstall gas pipingInstall condensate line trap and pipingMake electrical connectionsInstall other accessoriesPad--mounted installation —Prepare pad and unit supportsRig and place unitRemove duct covers and top skidInstall smoke detector return air sensor tubeInstall field--fabricated ductwork at unit duct openingsInstall outside air hoodInstall combustion air hoodInstall flue hoodInstall gas pipingInstall condensate line trap and pipingMake electrical connectionsInstall other accessoriesFrame--mounted installation —Frame--mounted applications generally follow thesequence for a curb installation. Adapt as required tosuit specific installation plan.Step 3 — Inspect unitInspect unit for transportation damage. File any claimwith transportation agency.Confirm before installation of unit that voltage, amperageand circuit protection requirements listed on unit dataplate agree with power supply provided.Locate the carton containing the outside air hood parts; seeFigs. 5 and 12. Do not remove carton until unit has beenrigged and located in final position.Step 4 — Provide Unit SupportRoof Curb Mount —Accessory roof curb details and dimensions are shown inFigs. 6, 7 and 8. Assemble and install accessory roof curbin accordance with instructions shipped with the curb.NOTE: The gasketing of the unit to the roof curb is criticalfor a watertight seal. Install gasket supplied with the roofcurb as shown in Figs. 6, 7 and 8. Improperly applied gasketcan also result in air leaks and poor unit performance.Curb should be level. This is necessary for unit drain tofunction properly. Unit leveling tolerances are show inFig. 9. Refer to Accessory Roof Curb InstallationInstructions for additional information as required.Install insulation, cant strips, roofing felt, and counterflashing as shown. Ductwork must be attached to curb andnot to the unit. Thru--the--base power connection must beinstalled before the unit is set on the roof curb. Iffield--installed thru--the--roof curb gas connections aredesired remove knockout in basepan located in the gassection, see Fig. 5 for location. Gas connections andpower connections to the unit must be field installed afterthe unit is installed on the roof curb.If electric and control wiring is to be routed through thebasepan, remove knockouts in basepan located in controlbox area of access panel; see Fig. 1, 2, or 3 for basepanknockout locations for location. Attach the serviceconnections to the basepan.Control BoxAccess PanelFilter andIndoor CoilAccess PanelIndoor BlowerAccess PanelGas HeatAccess Panel Compressor(each side)Hood Carton Location(rear access panel)C11154Fig. 5 -- Typical Access Panel and Compressor LocationsSlab Mount (Horizontal Units Only) —Provide a level concrete slab that extends a minimum of6–in. (150 mm) beyond unit cabinet. Install a gravel apronin front of condenser coil air inlet to prevent grass andfoliage from obstructing airflow.NOTE: Horizontal units may be installed on a roof curbif required.Alternate Unit Support (In Lieu of Curb or SlabMount) —A non--combustible sleeper rail can be used in the unitcurb support area. If sleeper rails cannot be used, supportthe long sides of the unit with a minimum of 4 equallyspaced 4--in. x 4--in. (102 mm x 102 mm) pads on eachside. Locate pads so that they support the rails. Make sureto avoid the fork openings.48HC