Service
WARNING
ELECTRICAL SHOCK, FIRE,
OR EXPLOSION HAZARD.
Failure to follow safety warnings exactly could result in dangerous operation, serious injury, death or property damage.
Improper servicing could result in dangerous opera- tion, serious injury, death, or property damage. Before servicing, disconnect all electrical power to furnace.
When servicing controls, label all wires prior to dis- connecting. Take care to reconnect wires correctly. Verify proper operation after servicing.
At the beginning of each heating season, system should be checked as follows by a qualified service technician: Blower
Check the blower wheel for debris and clean if necessary. The blower motors are prelubricated for extended bearing life. No further lubrication is needed.
WARNING
The blower access panel must be securely in place when the blower and burners are operating. Gas fumes, which could contain carbon monoxide, can be drawn into living space resulting in personal inju- ry or death.
Filters
All air filters are installed external to the unit. Filters should be inspected monthly. Clean or replace the filters when necessary to ensure proper furnace operation. Table 3 lists recommended filter sizes.
Exhaust and air intake pipes
Check the exhaust and air intake pipes and all connections for tightness and to make sure there is no blockage. NOTE − After any heavy snow, ice or frozen fog event the furnace vent pipes may become restricted. Always check the vent system and remove any snow or ice that may be obstructing the plastic intake or exhaust pipes. Electrical
1 − Check all wiring for loose connections.
2 − Check for the correct voltage at the furnace (furnace operating).
3 − Check amp−draw on the blower motor.
Motor Nameplate__________Actual__________
Winterizing and Condensate Trap Care 1 − Turn off power to the furnace.
2 − Have a shallow pan ready to empty condensate water.
3 − Remove the clean out cap from the condensate trap and empty water. Inspect the trap then reinstall the drain plug.
Cleaning Heat Exchanger
If cleaning the heat exchanger becomes necessary, follow the below procedures and refer to figure 1 when disassem- bling unit. Use papers or protective covering in front of fur- nace while removing heat exchanger assembly.
1 − Turn off electrical and gas supplies to the furnace.
2 − Remove the furnace access panels.
3 − Disconnect the 2 wires from the gas valve.
4 − Remove gas supply line connected to gas valve. Re- move gas valve/manifold assembly.
5 − Remove sensor wire from sensor. Disconnect
6 − Disconnect wires from flame roll−out switches.
7 − Loosen clamps at vent elbow. Disconnect condensate drain tubing from flue collar. and remove the vent el- bow.
8 − Remove four burner box screws at the vestibule panel and remove burner box. Set burner box assembly aside.
NOTE − If necessary, clean burners at this time. Follow procedures outlined in Burner Cleaning section.
9 − Mark and disconnect all combustion air pressure tub- ing from cold end header collector box.
10 − Mark and remove wires from pressure switches. Re- move pressure switches. Keep tubing attached to pressure switches.
11 − Disconnect the plug from the combustion air inducer. Remove two screws which secure combustion air in- ducer to collector box. Remove combustion air induc- er assembly. Remove ground wire from vest panel.
12 − Remove electrical junction box from the side of the fur- nace.
13 − Mark and disconnect any remaining wiring to heating compartment components. Disengage strain relief bushing and pull wiring and bushing through the hole in the blower deck.
14 − Remove the primary limit from the vestibule panel.
15 − Remove two screws from the front cabinet flange at the blower deck. Spread cabinet sides slightly to allow clearance for removal of heat exchanger.
16 − Remove screws along vestibule sides and bottom which secure vestibule panel and heat exchanger as- sembly to cabinet. Remove two screws from blower rail which secure bottom heat exchanger flange. Re- move heat exchanger from furnace cabinet.
17 − Back wash heat exchanger with soapy water solution or steam. If steam is used it must be below 275°F (135°C) .
18 − Thoroughly rinse and drain the heat exchanger. Soap solutions can be corrosive. Take care to rinse entire assembly.
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