Carrier 58MCB Installation, Start-up, And Operating Instructions Manual

Also see for 58MCB: User's information manual Service and maintenance instructions Owner's manual Service and maintenance instruction Nstallation, start-up, and operating instructions

Carrier 58MCB Installation, Start-up, And Operating Instructions Manual Manual pdf 22 page image

Flexible connections should be used between ductwork andfurnace to prevent transmission of vibration. Ductwork passingthrough unconditioned space should be insulated to enhancesystem performance. When air conditioning is used, a vaporbarrier is recommended.Maintain a 1-in. clearance from combustible materials to supply airductwork for a distance of 36-in. horizontally from the furnace.See NFPA 90B or local code for further requirements.For a furnace not equipped with a cooling coil, the outlet duct shallbe provided with a removable access panel. This opening shall beaccessible when the furnace is installed and shall be of such a sizethat the heat exchanger can be viewed for possible openings usinglight assistance or a probe can be inserted for sampling the airstream. The cover attachment shall prevent leaks.DUCTWORK ACOUSTICAL TREATMENTMetal duct systems that do not have a 90 degree elbow and 10 ftof main duct to the first branch take-off may require internalacoustical lining. As an alternative, fibrous ductwork may be usedif constructed and installed in accordance with the latest edition ofSMACNA construction standard on fibrous glass ducts. Bothacoustical lining and fibrous ductwork shall comply with NFPA90B as tested by UL Standard 181 for Class 1 Rigid air ducts.SUPPLY AIR CONNECTIONSUpflow FurnacesConnect supply-air duct to 3/4-in. flange on furnace supply-airoutlet. The supply-air duct attachment must ONLY be connectedto furnace supply-/outlet-air duct flanges or air conditioning coilcasing (when used). DO NOT cut main furnace casing to attachsupply side air duct, humidifier, or other accessories. All accesso-ries MUST be connected external to furnace main casing.Downflow FurnacesConnect supply-air duct to supply-air opening on furnace. Thesupply-air duct attachment must ONLY be connected to furnacesupply/outlet or air conditioning coil casing (when used), wheninstalled on non-combustible material. When installed on combus-tible material, supply-air duct attachment must ONLY be con-nected to an accessory subbase or factory approved air condition-ing coil casing. DO NOT cut main furnace casing to attach supplyside air duct, humidifier, or other accessories. All accessoriesMUST be connected external to furnace main casing. Supply airopening duct flanges must be modified per Fig. 24.Horizontal FurnacesConnect supply-air duct to supply air opening on furnace. Thesupply-air duct attachment must ONLY be connected to furnacesupply/outlet or air conditioning coil casing (when used). DO NOTcut main furnace casing to attach supply side air duct, humidifier,or other accessories. All accessories MUST be connected externalto furnace main casing.RETURN AIR CONNECTIONSThe furnace and its return air system shall be designed andinstalled so that negative pressure created by the air circulating fancannot affect another appliance’s combustion air supply or act tomix products of combustion with circulating air and the aircirculating fan of the furnace, if installed in an enclosure commu-nicating with another fuel-burning appliance not of the direct-venttype, shall be operable only when any door or panel covering anopening in the furnace fan compartment or in return air plenum onducts is in the closed position.FIRE HAZARDA failure to follow this warning could result in fire, personalinjury, or death.Never connect return-air ducts to the back of the furnace.Return-air duct connections on furnace side(s) permitted inupflow applications only.Upflow FurnacesThe return-air duct must be connected to end, sides (left or right),or a combination of end and side(s) of main furnace casing asshown in Fig. 2. Bypass humidifier may be attached into unusedside return air portion of the furnace casing. DO NOT connect anyportion of return-air duct to back of furnace casing.Downflow and Horizontal FurnacesThe return-air duct must be connected to end inlet openingprovided as shown in Fig. 2. DO NOT cut into casing sides or backto attach any portion of return-air duct. Bypass humidifier connec-tions should be made at ductwork or coil casing sides exterior tofurnace.Step 5—Filter ArrangementFIRE, CARBON MONOXIDE AND POISONINGHAZARDFailure to follow this warning could result in fire, personalinjury, or death.Never operate a unit without a filter or with filter access doorremoved.Factory-supplied washable framed filters are shipped in blowercompartment. Determine location for filter and relocate filterretaining wire if necessary. See Table 4 to determine correct filtersize for desired filter location. Table 4 indicates filter size,location, and quantity shipped with this furnace. See Fig. 2 forlocation and size of bottom and side return-air openings.CUT HAZARDFailure to follow this caution may result in minor personalinjury.Use care when cutting support rods in filters to protect againstflying pieces and sharp rod ends. Wear safety glasses, gloves,and appropriate protective clothing.Table 4—Filter InformationFURNACECASINGWIDTH (IN.)FILTER SIZE (IN.) FILTER TYPEFRAMEDSide Return†* Bottom Return*17-1/2 (1) 16 X 25 X 1 (1) 16 X 25 X 1 Cleanable21 (1) 16 X 25 X 1 (1) 20 X 25 X 1 Cleanable24-1/2 (1 or 2) 16 X 25 X 1 (1) 24 X 25 X 1 Cleanable* Factory-provided with the furnace. Filters may be field modified by cuttingfilter material and support rods (3) in filters. Alternate sizes and additionalfilters can be ordered from your distributor or dealer.† Upflow only. Alternate sizes and additional filters my be ordered from yourdealer.22→