Accurex XMPX Series Installation, Operation And Maintenance Manual

Accurex XMPX Series Installation, Operation And Maintenance Manual Manual pdf 7 page image

Rail and Roof Curb MountingRail Mounting and Layout• The unit may be installed on rails provided andinstalled by others. Ensure that rails are designedto handle the weight of the unit and provide properload distribution on building supports.• Make sure that rail positioning does not interferewith the supply air discharge opening on the unit.• Rails should run the width of the unit and extendbeyond the unit a minimum of 12 inches on eachside.• Set unit on rails.Roof Curb MountingRoof curb details, including duct location dimensions,are available on the model’s roof curb assemblyinstructions.Rooftop units require curbs to be mounted first. Theduct connections must be located so they will be clearof structural members of the building.1. Factory Supplied Roof CurbsRoof curbs are model GKD which are shippedin a knockdown kit (includes duct adapter) andrequire field assembly (by others). Assemblyinstructions are included with the curb.2. Install CurbLocate curb over roof opening and fasten inplace. (Refer to Recommended Roof Openings).Check that the diagonal dimensions are within±1/8 inch of each other and adjust as necessary.For proper coil drainage and unit operation, it isimportant that the installation be level. Shim asrequired to level.3. Install DuctworkInstallation of all ducts should be donein accordance with SMACNA and AMCAguidelines. Duct adapter provided to supportducts prior to setting the unit.4. Set the UnitLift unit to a point directlyabove the curb andduct openings.Guideunit whileloweringto alignwith ductopenings.Roof curbsfit inside theunit base.Make surethe unit isproperlyseated onthe curband is level.No openings directly beneath the unit discharge.Ductwork ConnectionsThe supply fan in this unit is a plenum-type fan. Thedischarge opening dimensions are provided in thechart below. For proper fan performance, match theduct size to the dimensions indicated. Installationof all ducts should be done in accordance with BestPractices and SMACNA.Supply Air Duct Opening Dimensions(height x width; inches)ModelDownblast Discharge Horizontal DischargeIndirectGasElectricHeatIndirectGasElectricHeatMPX-H14 28.9 x 25.9 24.9 x 25.9 28.5 x 27.5 28.5 x 27.5MPX-H24 33.9 x 25.9 33.9 x 25.9 38 x 38 35.9 x 27MPX-H34 33.9 x 25.9 36.3 x 28.9 38 x 38 39 x 40NOTEDownblast Discharge Ductwork - wheneverdownblast discharge is used, the ductwork directlybeneath the unit must be connected with either a “T”or an “L” configuration and the area directly beneaththe heat source must not have any openings suchas louvers or grates.7Model MPX Make-Up Air UnitModel XMPX Make-Up Air Unit