Carrier 58MSA Service And Maintenance Instructions

Also see for 58MSA Series: Service and maintenance instructions User manual Instruction manual Installation, start-up, and operating instructions Installation, start-up, and operating instructions

Contents

Carrier 58MSA Service And Maintenance Instructions Manual pdf 8 page image

The igniter is fragile. DO NOT allow it to hit the side of theburner box opening while removing or replacing it.b. Inspect igniter for a white area indicating a crack may bepresent. If found, replace igniter.NOTE: A small crack cannot be seen on a new igniter. After aperiod of operation, a white area will be visible around the crack.c. If replacement is required, replace igniter on igniter bracketexternal to furnace to avoid damage as the silicon portion isvery brittle and will easily crack or shatter.d. To remove igniter from igniter bracket, remove screwholding igniter ceramic block to bracket and pull ceramicblock out of bracket.6. To replace igniter/igniter assembly, reverse items 5a through5d.7. Reconnect igniter wire connection.8. Turn on gas and electrical supplies to furnace.9. Verify igniter operation by initiating furnace control boardself-test feature or by cycling thermostat.10. Replace main furnace door.Step 7—Electrical Controls and WiringThere may be more than 1 electrical supply to the furnace.Check accessories and cooling unit for additional electricalsupplies.The electrical ground and polarity for 115-v wiring must bemaintained properly. Refer to Fig. 11 for field wiring informationand to Fig. 16 for furnace wiring information.NOTE: If the polarity is not correct, the STATUS LED on thefurnace control board will flash rapidly and prevent the furnacefrom operating. The control system also requires an earth groundfor proper operation of the furnace control board and flame sensor.The 24-v circuit contains an automotive-type, 3-amp fuse locatedon the furnace control board. (See Fig. 12.) Any direct shorts of the24-v wiring during installation, service, or maintenance will causethis fuse to blow. If fuse replacement is required, use ONLY a3-amp fuse of identical size. The control LED will flash statuscode 24 when fuse needs to be replaced.With power to the unit disconnected, check all electrical connec-tions for tightness. Tighten all screws on electrical connections. Ifany smoky or burned connections are found, disassemble theconnection, clean all parts, strip wire, and reassemble properly andsecurely.Reconnect electrical supply to unit and observe unit through 1complete operating cycle for proper operation.If this furnace is to be operated in an unconditioned spacewhere the ambient temperatures may be 32°F or lower, freezeprotection measures must be taken. (See Fig. 13.)Step 8—Checking Heat Tape Operation (If Applicable)In applications where the ambient temperature around the furnaceis 32°F or lower, freeze protection measures are required. If heattape has been applied, check to ensure it will operate when lowtemperatures are present.NOTE: Heat tape, when used, should be wrapped around thecondensate drain trap and drain line. There is no need to use heattape within the furnace casing. Most heat tapes are temperatureactivated, and it is not practical to verify the actual heating of thetape. Check the following:1. Check for signs of physical damage to heat tape such as nicks,cuts, abrasions, gnawing by animals, etc.2. Check for discolored heat tape insulation. If any damage ordiscolored insulation is evident, replace heat tape.3. Check that heat tape power supply circuit is on.Step 9—WinterizingFreezing condensate left in the furnace will damage thefurnace.If the furnace will be off for an extended period of time in astructure where the temperature will drop to 32°F or below,winterize as follows:1. Turn off electrical supply to furnace.2. Remove main furnace door.Fig. 9—Burner FlameA89020BURNER FLAMEBURNERMANIFOLDFig. 10—Gasket on Collector BoxA93081RTVPAM8