Burner Flame; Flue Passage And Vent Inspection; Heat Exchanger Assembly; Turning Off Gas To Furnace - Lennox SGA036 User's Information Manual

1− Set thermostat to lowest setting.
2− Turn off all electrical power to furnace.
3− This furnace is equipped with an ignition device which
automatically lights the burner. Do not try to light the
burner by hand.
4− Open or remove the heat section access panel.
5− Turn the knob on the gas valve clockwise
OFF". Do not force.
6− Wait five (5) minutes to clear out any gas. If you then
smell gas, STOP!
gas supplier from a neighbor's phone. Follow the gas
supplier's instructions. If you do not smell gas, go to
the next step.
7− Turn the knob on the gas valve counterclockwise
to ON". Do not force.
8− Close or replace the heat section access panel.
9− Turn on all electrical power to furnace.
10− Set thermostat to desired setting.
11− The ignition sequence will start.
12− If the furnace does not light the first time (gas line not
fully purged), it will attempt up to two more ignitions
before locking out.
13− If lockout occurs, repeat steps 1 through 10.
14− If the furnace will not operate, follow the instructions
Turning Off Gas to Furnace" and call your service
technician or gas supplier.

Turning Off Gas to Furnace

1− If using an electromechanical thermostat, set to the
lowest setting.
2− Before performing any service, turn off all electrical
power to the furnace.
3− Open or remove the heat section access panel.
4− Turn the knob on the gas valve clockwise
OFF". Do not force.
5− Replace heat section access panel.
WARNING
Danger of explosion. Can cause injury or
death. Do not attempt to light manually.
Unit has a direct spark ignition system.
to
Immediately call your
to
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Burner Flame

WARNING
Danger of explosion and fire. Can cause
injury or product or property damage.
Periodically inspect burner flame to en-
sure proper unit operation.
The primary air is permanently set for normal operation.
The flame will be basically blue with some clear yellow
streaking in the end of the flame. Inspect burner flame
periodically during heating season using inspection port
provided on the burner access panel.

Flue Passage And Vent Inspection

Annually, before heating season, inspect combustion air
louvers, vent cap, heat exchanger, burners and
combustion air blower for corrosion, deterioration or
deposits of debris. Remove any obstructions or blockage.
See figures 3 and 4.

HEAT EXCHANGER ASSEMBLY

036 & 060 UNITS
HEAT
EXCHANGER
TUBE
COMBUSTION
AIR INDUCER
GAS VALVE
BURNER
FIGURE 3
BAFFLE
VENT
CONNECTOR