Carrier WEATHER MASTER P4 Installation Instructions Manual

Contents

2INSTALLATIONStep 1 — Perform Jobsite Survey — Completethe following checks before installation.1. Consult local building codes and the NEC (NationalElectrical Code) (ANSI/NFPA [American National Stan-dards Institute/National Fire Protection Association] 70)for special installation requirements.2. Determine unit location (from project plans) or select unitlocation.3. Check for possible overhead obstructions which may in-terfere with unit lifting or rigging.Step 2 — Place Unit — Inspect unit for transportationdamage. File claim with transportation agency.Provide clearance around and above unit for airflow, safety,and service access. Do not restrict top (area above condenserfans) in any way. Allow at least 6 ft on all sides for rated perfor-mance, code compliance, and service. On units equipped withpower exhaust option, high velocity air is exhausted out thehood. Unit should be positioned with at least 10 ft clearance be-tween the exhaust hood and any obstruction.Check unit dimensional drawings for unit arrangement andminimum performance and service clearances.Do not install unit in an indoor location. Do not locate air in-lets near exhaust vents or other sources of contaminated air.Although unit is weatherproof, guard against water fromhigher level runoff and overhangs.Level by using unit frame as a reference. Physical data isshown in Tables 1A-9.Step 3 — Roof Mount Unit — Check building codesfor weight distribution requirements. Unit weight is shown inTables 1A-1C and 5. Unit may be mounted on class A, B, or Croofing material.ROOF CURB — Assemble and install roof curb as describedin instructions shipped with the accessory. Accessory roof curband information required to field fabricate a roof curb is shownin Fig. 1-5. Install insulation, cant strips, roofing and counterflashing as required. For unit condensate drain to functionproperly, curb must be level or within tolerances shown inFig. 1-5.STEEL BEAMS — If roof curb is not used, support unit withsteel beams along its entire length and then support steel as re-quired. As a minimum, unit must be supported across its widthat each lifting lug location.Step 4 — Slab Mount Unit — Provide a level con-crete slab that extends beyond unit cabinet at least 6 inches.Make a slab 8 in. thick with 4 in. above grade. Use gravelapron in front of condenser coil air inlet to prevent grass andfoliage from obstructing airflow. Ensure that slab is ofsufficient height to allow for condensate trap of 4 in. on sizes030-070 or 7 in. on sizes 075-100.Step 5 — Install Curb GasketingSIZE 030-060 UNITS — After ductwork has been connectedto the roof curb, attach adhesive-backed gasketing on all endrails, cross rails, and duct rails. Be sure all joints and corners ofgasket are square and flush to prevent possible water leaks.Follow all applicable building codes.SIZE 070-100 UNITS — After ductwork has been connectedto the roof curb, apply gasket material (1/2-in. thick x 11/2-in.wide neoprene) where indicated.Single-Thickness Gasketing (See Fig. 6-8 for Item Num-bers) — Apply gasketing in the following places:1. Along both side rails (1) — 2 places, full length2. Along return air end rail (2) — 1 place3. Around return air internal duct flange (3) — 1 or 2 places4. Around supply air internal duct flanges (4) — 3 placesDouble-Thickness Gasketing (See Fig. 6 and 8 and DetailA-A) — Locate a line 93/4-in. from the supply air end of theaccessory curb. Apply a double-thickness of gasket materialalong line per detail A-A.NOTE: Do not apply gasket material along the outside edge ofthe curb (area “X”). This pan area of the curb extends outbeneath the end of the unit’s air handler section; applying gas-ket here develops a potential water trap area on top of the curb.Condenser Section Roof Curb (See Fig. 7) — Apply single-thickness gasket along both side rails (5).Step 6 — Install Field-Fabricated DuctworkThe 48P2,P3 units are designed for vertical supply/returnonly. Field-fabricated ductwork must be attached to the roofcurb, or to the support steel, prior to the final rigging and instal-lation of the unit. Supply and return duct dimensions are shownin Fig. 1-3.To attach ductwork to roof curb, insert duct approximately 10to 11 in. up into roof curb. Connect ductwork to 14-gage roofcurb material with sheet metal screws driven from inside the duct.Secure all ducts to the building structure, using flexible ductconnectors between roof curbs and ducts as required. Ductspassing through an unconditioned space must be insulated andcovered with a vapor barrier. Outlet grilles must not lie directlybelow unit discharge.Design supply duct strong enough to handle expected staticpressures.Step 7 — Rig Unit — Do not drop unit; keep upright.Use spreader bars over unit to prevent sling or cable damage.Sheets of plywood placed along the condenser coils will pro-vide additional protection. All lifting lugs MUST be used whenlifting unit. Level by using unit frame as a reference. See Fig. 9and 10 for information. Unit and accessory weights are shownin Tables 1A-1C and 5. Weight distribution and center of gravi-ty can be found in Fig. 11.CAUTIONDisconnect gas piping from units when leak testing at pres-sures greater than 0.5 psig. Pressures greater than 0.5 psigwill cause gas valve damage resulting in a hazardouscondition. If gas valve is subjected to pressure greater than0.5 psig, it must be replaced. When pressure testing field-supplied gas piping at pressures of 0.5 psig or less, the unitconnected to such piping must be isolated by manuallyclosing the gas valve.CAUTIONDo not lift unit with forklift truck. Move unit with over-head rigging only.WARNINGFor vertical supply and return units, tools or parts coulddrop into ductwork and cause an injury. Install a 90-degreeelbow in the supply and return ductwork between the unitand the conditioned space. If a 90-degree elbow cannot beinstalled, then a grille of sufficient strength and densityshould be installed to prevent objects from falling into theconditioned space. Failure to follow these instructionscould result in personal injury or property damage due tofalling objects.