User's Manual

Page 4
your Lennox dealer for an inspection by a licensed profes-
sional service technician (or equivalent).
DANGER
Danger of explosion.
There are circumstances in which odorant used with
LP/propane gas can lose its scent. In case of a leak,
LP/propane gas will settle close to the floor and may
be difficult to smell. An LP/propane leak detector
should be installed in all LP applications.
Do not attempt to bleed the gas lines of air. Call your
local gas provider.
Start−Up & Operation Information
WARNING
If you do not follow these instructions exactly, a fire
or explosion may result causing property damage,
personal injury or death.
BEFORE PLACING THE UNIT INTO OPERATION, 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.
The gas valve on the 180DFE will be equipped with a gas
control switch. Use only your hand to move the switch.
Never use tools. If the switch will not move by hand, do
not try to repair it. Call a licensed professional service
technician (or equivalent). Force or attempted repair
may result in a fire or explosion.
Placing the ML180DFE furnace into operation:
ML180DFE units are equipped with an ignition system.
Do not
attempt to manually light burners on this furnace.
Each time the thermostat calls for heat, the burners will
automatically light. The ignitor does not get hot when
there is no call for heat on units with this ignition system.
Operating the Gas Valve (Figure 2)
1 − STOP! Read the safety information at the beginning of
this section.
2 − Set the thermostat to the lowest setting.
3 − Turn off all electrical power to the unit.
4 − This furnace is equipped with an ignition device which
automatically lights the burners. Do not try to light the
burners by hand.
5 − Remove the heating access panel.
6 − Move switch on gas valve to OFF. See figure 2.
7 − Wait five 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 instruc-
tions. If you do not smell gas go to next step.
8 − Move switch on gas valve to ON. See figure 2.
GAS VALVE SHOWN IN ON POSITION
MANIFOLD
PRESSURE
OUTLET
INLET
PRESSURE PORT
MANIFOLD
PRESSURE
ADJUSTMENT
SCREW
FIGURE 2
9 − Replace the heating access panel.
10 − Turn on all electrical power to to the unit.
11 − Set the thermostat to desired setting.
NOTE − When unit is initially started, steps 1 through 11
may need to be repeated to purge air from gas line.
12 − If the appliance will not operate, follow the section
Turning Off Gas to the Unit" and call your licensed
professional service technician (or equivalent).
Turning Off Gas to the Unit
1 − Set the thermostat to the lowest setting.
2 − Turn off all electrical power to the unit if service is to be
performed.
3 − Remove the heating access panel.
4 − Move switch on gas valve OFF.
5 − Replace the upper access panel.