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G40UH(X) Parts Identification
DURALOK
TM
HEAT
EXCHANGER
ASSEMBLY
UPPER ACCESS
PANEL
BURNERS
BLOWER
MOTOR
GAS
MANIFOLD
CABINET
CONTROL BOX
GAS
VALVE
COMBUSTION AIR
PROVING
(PRESSURE) SWITCH
COMBUSTION AIR
INDUCER
BLOWER ACCESS
PANEL
FLUE
COLLAR
TOP CAP
SURELIGHT
CONTROL BOARD
NAMEPLATE
FIGURE 1
WARNING
Product contains fiberglass wool.
Disturbing the insulation in this product during
installation, maintenance, or repair will expose you
to fiberglass wool. Breathing this may cause lung
cancer. (Fiberglass wool is known to the State of Cal-
ifornia to cause cancer.)
Fiberglass wool may also cause respiratory, skin,
and eye irritation.
To reduce exposure to this substance or for further
information, consult material safety data sheets
available from address shown below, or contact your
supervisor.
Lennox Industries Inc.
P.O. Box 799900
Dallas, TX 75379-9900
NOTE - This manual must be left with the equipment
user.
WARNING
Do not set thermostat below 60°F (16°C) in heating
mode. Setting thermostat below 60°F (16°C) reduces
the number of heating cycles. Damage to the unit
may occur that is not covered by the warranty.
WARNING
If overheating occurs or if gas supply fails to shut off,
shut off the manual gas valve to the appliance before
shutting off electrical supply.
CAUTION
Before attempting to perform any service or mainte-
nance, turn the electrical power to unit OFF at the
disconnect switch.