506725-01
Page 42 of 48
Issue 1109
Service
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.
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 injury or death.
WARNING
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 pipe
s.
Electrical
1. Check all wiring for loose connections.
2. Check for the correct voltage at the furnace (furnace
operating). Correct voltage is 120 VAC ± 10%.
3. Check amp-draw on the blower motor with the blower
compartment access panel in place.
Motor Nameplate__________Actual__________
ELECTRICAL SHOCK, FIRE,
OR EXPLOSION HAZARD.
WARNING
Failure to follow safety warnings exactly could result in
dangerous operation, serious injury, death or property
damage.
Improper servicing could result in dangerous operation,
serious injury, death, or property damage.
Before servicing, disconnect all electrical power to
furnace.
When servicing controls, label all wires prior to
disconnecting. Take care to reconnect wires correctly.
Verify proper operation after servicing.
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 clean
out cap.
Cleaning Heat Exchanger
If cleaning the heat exchanger becomes necessary, follow
the below procedures and refer to Figure 1 when
disassembling unit. Use papers or protective covering in
front of furnace 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.
Remove gas valve/manifold assembly.
5. Remove sensor wire from sensor. Disconnect 2 pin
plug from the ignitor.
6. Disconnect wires from flame rollout switches.
7. Loosen clamps at vent elbow. Disconnect condensate
drain tubing from flue collar and remove the vent elbow.
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 tubing
from cold end header collector box.
10. Mark and remove wires from pressure switches.
Remove pressure switches. Keep tubing attached to
pressure switches.
11. Disconnect the plug from the combustion air inducer.
Remove two screws which secure combustion air
inducer to collector box. Remove combustion air inducer
assembly. Remove ground wire from vest panel.
12. Remove electrical junction box from the side of the
furnace.
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 assembly
to cabinet. Remove two screws from blower rail which
secure bottom heat exchanger flange. Remove 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.
