UPFLOW FURNACE SIDE RETURN AIR
BURNER FLAME
FLAME APPEARS BLUE IF BURNING NAT. GAS; BLUE/ YELLOW FOR PROPANE.
BURNER
FLAME
HEAT
EXCHANGER
TUBE
VEST
PANEL
FIGURE 3
Fan
Check and clean fan wheel for any debris. Fan motor is
prelubricated for extended bearing life. No further lubrica% tion is needed.
WARNING
Fan door must be securely in place when fan and burners are operating. Gas fumes, which could contain carbon monoxide, can be drawn into living space resulting in personal injury or death.
Burner Flame
The G24MCE burner flame is not adjustable; however, the flame should be inspected at the beginning of each
heating season and burners should be cleaned, if neces%
sary. Burner flame should be blue when burning natural gas, blue/yellow when burning propane gas.
FIGURE 4
Venting System Inspection
Annually (before heating season) inspect furnace venting system, vent cap, heat exchanger and burners for corro% sion, deterioration, or deposits of debris. Remove any ob% structions.
Contact your Lennox dealer for a periodic unit inspection by a qualified gas service engineer.
Capillary Tube Limit Switch
Your Lennox furnace is equipped with a manually%reset capillary tube limit switch which shuts off the gas supply to the furnace in the event of inadequate supply air (high air temperature). It is located on the vestibule panel near the gas valve. To reset this control, push the switch on the face of the control sideways. If this switch opens again, consult a qualified gas service engineer.
Control Board Lockouts
Several types of control board lockout modes exist on this furnace. When in one of these modes, the control board will not allow the furnace to start. The two modes that can be manually reset are: a •Watchguard lockout mode," and a •Hard lockout mode."
To reset the •Watchguard mode," manually switch the ther% mostat from HEAT to OFF and then back to HEAT again. (Note - This lockout mode will also automatically reset after a 60 minute lockout period.)
The •Hard lockout mode" can be reset by turning the elec% trical power OFF and then back ON again.
If either of these two lockouts reoccur, or if the original lock% out cannot be reset, call a qualified gas service engineer.
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