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Temperature Rise
Check temperature rise and, if necessary, adjust blower
speed to maintain temperature rise within range shown on
unit rating plate.
Electrical
1 - Check all wiring for loose connections.
2 - Check circuit breaker located on unit control box.
3 - Check for correct voltage at the furnace (furnace operĆ
ating).
4 - Check amp-draw on blower motor.
Motor Nameplate __________Actual__________.
NOTE - Do not secure electrical conduit directly to ducting
or structure.
Blower Speeds
Refer to blower speed selection chart on unit wiring dia-
gram.
NOTE - CFM readings are taken external to unit with a dry
evaporator coil, filter installed and without any other accesĆ
sories.
Electronic Ignition
The SureLight
t
integrated control has an added internal
watchguard feature. The feature serves as an automatic
reset device for ignition controls locked out because the
burner has failed to light. This type of nuisance lockout is
usually attributed to low gas line pressure. After one hour of
continuous thermostat demand for heat, the watchguard
will break and remake thermostat demand to the furnace
and automatically reset the control to relight the furnace.
Burner Flame
Burner Flame
-- Start burner and allow to operate for a few
minutes to establish normal burning conditions. Check
burner flame by observation. Flame should be predomiĆ
nantly blue and strong in appearance.
Check burner flame periodically to ensure proper operation.
Service
WARNING
Disconnect power before servicing unit.
CAUTION
Label all wires prior to disconnection when serv-
icing controls. Wiring errors can cause improper
and dangerous operation. Verify proper operation
after servicing.
Annual Service
At the beginning of each heating season, system should be
checked as follows by a qualified service technician:
Electrical
1 - Check all wiring for loose connections.
2 - Check circuit breaker located on unit control box.
3 - Check for correct voltage at unit (unit operating).
4 - Check amp-draw on blower motor.
Motor Nameplate_________Actual_________
5 - Check to see that heat (if applicable) is operating.
Blower
Check the blower wheels for debris and clean if necessary.
The blower motors are prelubricated for ex-tended bearing
life. No further lubrication is needed.
Filters
1 - Filters must be cleaned or replaced when dirty to as-
sure proper furnace operation.
2 - Reusable foam filters used with G26 can be washed
with water and mild detergent. When dry, they should
be sprayed with filter handicoater prior to reinstallaĆ
tion. Filter handicoater is RP Products coating no. 418
and is available as Lennox part no. P-8-5069.
3 - If replacement is necessary, order Lennox part no.
31J81 for 14 inch x 25 inch (356 x 635mm) filter for
G26-50 and -75 units and P-8-7831 for 20 inch x 25
inch (508 x 635mm) filter for G26Q4/5-75, G26-100
and -125 units.
Intake and Exhaust Lines
Check intake and exhaust lines and all connections for
tightness and make sure there is no blockage. Also check
condensate line for free flow during operation.
Insulation
Outdoor piping insulation should be inspected yearly for
deterioration. If necessary, replace with same materials.
Winterizing and Condensate Trap Care
1 - Turn off power to unit.
2 - Have a shallow pan ready to empty condensate water.
Avoid spilling water into the control box.
3 - Remove clamp from flue assembly and remove boot
or cap. Empty water from cap. Visually inspect bottom
of flue assembly. Replace boot and clamp.
4 - Remove boot from condensate trap and empty water.
Inspect trap then replace boot.
Cleaning DuralokPlus
TM
Heat Exchanger
If it is necessary to clean the heat exchanger, follow the proĆ
cedure below and refer to figure 1 when disassembling the
unit. Use papers or protective covering in front of furnace
while removing heat exchanger assembly.
1 - Turn off electrical and gas power supplies to furnace.
2 - Remove upper and lower furnace access panels.
3 - Remove four screws around air intake fitting and lift inĆ
take pipe up and away.
4 - Loosen hose clamp securing top of flue transition to
bottom of flue collar. Remove screw securing flue colĆ
lar to top cap and lift exhaust pipe and flue collar up
and away.
5 - If electrical field makeĆup box is located inside the unit,
it must be removed.
6 - Remove gas supply line connected to gas valve.
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