Carrier DOWNFLOW HORIZONTAL 2-SPEED, 2-STAGE 58TMA Install And Operation Instructions

Contents

Carrier DOWNFLOW HORIZONTAL 2-SPEED, 2-STAGE 58TMA Install And Operation Instructions Manual pdf 5 page image

installed in that space. A confined space MUST have provisionsfor supplying air for combustion, ventilation, and dilution of fluegases using 1 of the following methods. (See Fig. 3 and Table 2.)NOTE: In determining free area of an opening, the blockingeffect of louvers, grilles, and screens must be considered. If freearea of louver or grille design is unknown, assume that woodlouvers have a 20 percent free area and metal louvers or grilleshave a 60 percent free area. Screens, when used, must not besmaller than 1/4-in. mesh. Louvers and grilles must be constructedso they cannot be closed.The size of the openings depends upon whether air comes fromoutside of the structure or an unconfined space inside the structure.1. All air from inside the structure requires 2 openings (forstructures not usually tight):a. Each opening MUST have at least 1 sq in. of free area per1000 Btuh of total input for all equipment within theconfined space, but not less than 100 sq in. per opening.(See Fig. 3 and Table 2.) The minimum dimension of airopenings shall not be less than 3 in.b. If the building is constructed unusually tight, a permanentopening directly communicating with the outdoors shall beprovided. See item 2 below.c. If furnace is installed on a raised platform to provide areturn-air plenum, and return air is taken directly fromhallway or space adjacent to furnace, all air for combustionmust come from outdoors.2. Air from outside the structure requires 1 of the followingmethods:a. If combustion air is taken from outdoors through 2 verticalducts, the openings and ducts MUST have at least 1 sq in.of free area per 4000 Btuh of total input for all equipmentwithin the confined space. (See Fig. 4 and Table 2.)b. If combustion air is taken from outdoors through 2 hori-zontal ducts, the openings and ducts MUST have at least 1sq in. of free area per 2000 Btuh of total input for allequipment within the confined space. (See Fig. 4 and Table2.)c. If combustion air is taken from outdoors through a singleopening or duct (horizontal or vertical) commencing within12 in. of the top of the confined space, opening and ductMUST have at least 1 sq in. of free area per 3000 Btuh ofthe total input for all equipment within the confined spaceand not less than the sum of the areas of all vent connectorsin the confined space. (See Fig. 4 and Table 2.) Equipmentclearances to the structure shall be at least 1 in. from thesides and back and 6 in. from the front of the appliances.When ducts are used, they must be of the same cross-sectional areaas the free area of the openings to which they connect. Theminimum dimension of ducts must not be less than 3 in. (See Fig.4.)Step 3—Supply-Air Plenum Installation (Downflow)DOWNFLOW INSTALLATIONNOTE: This furnace is approved for use on combustible flooringwhen manufacturer’s accessory floor base Part No.Fig. 3—Confined Space: Air for Combustion andVentilation from an Unconfined SpaceA93387RETURNAIR6″ MIN(FRONT) †SUPPLY AIRVENT THROUGH ROOF(CATEGORY I)1 SQ IN.PER 1000BTUH* IN DOOROR WALL12″ MAX1 SQ IN.PER 1000BTUH* IN DOOROR WALL12″ MAXINTERIORHEATEDSPACE* Minimum opening size is 100 sq in. withminimum dimensions of 3 in.† Minimum of 3 in. when type B-1 vent is used.UNCONFINEDSPACEFig. 4—Confined Space: Air for Combustion andVentilation from OutdoorsA93388DUCTS TOOUTDOORS1 SQ IN.PER 4000BTUH *RETURNAIR VENTTHROUGHROOF(CATEGORY I)DBACE1 SQ IN.PER 4000BTUHDUCTTOOUTDOORSSUPPLY AIR1 SQ IN.PER 2000BTUH*DUCTSTOOUTSIDE12″ MAX12″ MAXCONFINEDSPACE12″MAX12″MAX1 SQ IN.PER 4000BTUH *OUTDOORS1 SQ IN.PER 4000BTUH *1 SQ IN.PER 2000BTUH*12″ MAXUse any of the followingcombinations of openings:A & B C & D D & E F & GNOTE:* Minimum dimensions of 3 in.FG5→