Lennox ZGB Series Unit Information page 36

C-Heating Startup
FOR YOUR SAFETY READ BEFORE LIGHTING
BEFORE LIGHTING smell all around the appliance area
for gas. Be sure to smell next to the floor because some
gas is heavier than air and will settle on the floor.
Use only your hand to push in or turn the gas control knob.
Never use tools. If the knob will not push in or turn by
hand, do not try to repair it, call a qualified service tech-
nician. Force or attempted repair may result in a fire or
explosion.
In case of a safety shutdown, move thermostat switch to
OFF and return the thermostat switch to HEAT to reset
ignition control
WARNING
Danger of explosion. Can cause injury or
death. Do not attempt to light manually.
Unit has a direct spark ignition system.
WARNING
Danger of explosion and fire. Can cause
injury or product or property damage. You
must follow these instructions exactly.
Gas Valve Operation (figure 14 and 15)
1 - Set thermostat to lowest setting.
2 - Turn off all electrical power to appliance.
3 - This appliance 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 - Move gas valve switch to OFF. See figure 14 or 15.
6 - Wait five (5) minutes to clear out any gas. If you
then smell gas, STOP! Immediately call your 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 - Move gas valve switch to ON. See figure 14 or 15.
8 - Close or replace the heat section access panel.
9 - Turn on all electrical power to appliance.
10 - Set thermostat to desired setting.
NOTE - When unit is initially started, steps 1 through
9 may need to be repeated to purge air from gas
line.
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 appliance will not operate, follow the
instructions "Turning Off Gas to Appliance" and call
your service technician or gas supplier.
MANIFOLD
PRESSURE
ADJUSTMENT
SCREW
INLET
PRESSURE
PORT
Gas valve shown in ON position.
White Rodgers 36J54 Gas Valve
INLET
PRESSURE
TAP
Gas valve shown in OFF position.
Turning Off Gas to Appliance
1 - If using an electromechanical thermostat, set to the
lowest setting.
2 - Before performing any service, turn off all electrical
power to the appliance.
3 - Open or remove the heat section access panel.
4 - Turn the knob on the gas valve to "OFF". Do not
force.
D-Safety or Emergency Shutdown
Turn off power to the unit. Close manual and main gas
valves.
Page 36
FIGURE 14
Two-Stage
MANIFOLD HIGH FIRE
PRESSURE TAP ADJUSTMENT
LOW FIRE
ADJUSTMENT
FIGURE 15
MANIFOLD
PRESSURE
OUTLET