Lennox ML195UH SERIES User's Information Manual page 4

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 ML195UH 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 re-
pair may result in a fire or explosion.
Placing the ML195UH furnace into operation:
ML195UH 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 upper 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.
MANIFOLD
PRESSURE
ADJUSTMENT
SCREW
GAS VALVE SHOWN IN ON POSITION
9 − Replace the upper 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
If overheating occurs or if gas supply fails to shut off,
shut off the manual gas valve to the furnace before
shutting off electrical supply.
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 upper access panel.
4 − Move switch on gas valve OFF.
5 − Replace the upper access panel.
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.
Page 4
MANIFOLD
PRESSURE
OUTLET
FIGURE 2
WARNING
WARNING