Lennox Allied Air A95UH1D - Service

507270-03 Page 57 of 60Issue 1917
Service
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 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.
WARNING
At the beginning of each heating season, system should
be checked as follows by a qualied service technician:
Blower
Check the blower wheel for debris and clean if necessary.
The blower motors are pre-lubricated 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 lters are installed external to the unit. Filters should
be inspected monthly. Clean or replace the lters when
necessary to ensure proper furnace operation. Table 1 lists
recommended lter 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 (with
furnace operating). Correct voltage is 120 VAC ± 10%
3. Check amp-draw on the blower motor with the blower
access panel in place.
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
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 burner access panel.
3. Mark all gas valve wires and disconnect them from
valve.
4. Remove gas supply line connected to gas valve.
5. Remove sensor wire from ame sensor. Disconnect
2–pin plug from the ignitor.
6. Disconnect wires from ame rollout switches.
7. Remove four burner assembly screws at the vestibule
panel and remove gas valve /manifold and burner box
as a single unit.
8. If necessary, clean burners at this time. Follow
procedures outlined in Burner Cleaning section.
9. Remove the clean-out cap on trap and drain. Replace
cap.
10. Disconnect condensate drain line from the condensate
trap. Remove condensate trap (it may be necessary to
cut drain pipe). Remove the 1/2” NPT tting from the
cold end header box. Disconnect drain tubes from cold
end header collector box.
11. Disconnect condensate drain tubes from ue collar.
Remove screws that secures ue collar in place.
Remove ue collar. It may be necessary to cut the
exiting exhaust pipe for removal of the tting.
12. Loosen two clamps from exible no-hub exhaust collar.
13. Disconnect the 2–pin plug from the combustion air
inducer. Remove screws which secure combustion
air inducer to collector box. Remove combustion air
inducer assembly. Remove ground wire.
14. Mark and disconnect all combustion air pressure
tubing from cold end header collector box.
15. Mark and remove wires from pressure switch. Remove
pressure switch. Keep tubing attached to pressure
switch.
16. Remove electrical junction box from the side of the
furnace.
17. Remove blower access panel.
18. 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.