Lennox EL195UHE - ELECTRICAL GROUNDING AND VOLTAGE VERIFICATION; GROUNDING AND VOLTAGE CHECKS FOR INTEGRATED CONTROL

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Priming Condensate Trap
The condensate trap should be primed with water prior
to start-up to ensure proper condensate drainage. Either
pour 10 . oz. (300 ml) of water into the trap, or follow
these steps to prime the trap:
1 - Follow the lighting instructions to place the unit into
operation.
2 - Set the thermostat to initiate a heating demand.
3 - Allow the burners to re for approximately 3 minutes.
4 - Adjust the thermostat to deactivate the heating
demand.
5 - Wait for the combustion air inducer to stop. Set the
thermostat to initiate a heating demand and again
allow the burners to re for approximately 3 minutes.
6 - Adjust the thermostat to deactivate the heating
demand and wait for the combustion air inducer to
stop. At this point, the trap should be primed with
sufcient water to ensure proper condensate drain
operation.
WARNING
If you do not follow these instructions exactly, a re or
explosion may result causing property damage, personal
injury or death.
Gas Valve Operation (Figure 60)
1 - STOP! Read the safety information at the beginning
of his 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 access panel.
6 - Move gas valve switch to OFF. See gure 60.
7 - Wait ve 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 next step.
8 - Move gas valve switch to ON. See gure 60.
GAS VALVE SHOWN IN ON POSITION
MANIFOLD
PRESSURE
OUTLET
PORT
INLET
PRESSURE
PORT
MANIFOLD
PRESSURE
ADJUSTMENT
SCREW
FIGURE 60
9 - Replace the 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
instructions “Turning Off Gas to Unit” and call your
service technician or gas supplier.
Turning Off Gas to 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 access panel.
4 - Move gas valve switch to OFF.
5 - Replace the access panel.
Failure To Operate
If the unit fails to operate, check the following:
1 - Is the thermostat calling for heat?
2 - Are access panels securely in place?
3 - Is the main disconnect switch closed?
4 - Is there a blown fuse or tripped breaker?
5 - Is the lter dirty or plugged? Dirty or plugged lters
will cause the limit control to shut the unit off.
6 - Is gas turned on at the meter?
7 - Is the manual main shut-off valve open?
8 - Is the internal manual shut-off valve open?
9 - Is the unit ignition system in lockout? If the unit locks
out again, inspect the unit for blockages.
Heating Sequence Of Operation
1 - When thermostat calls for heat, combustion air
inducer starts.
2 - Combustion air pressure switch proves blower
operation. Switch is factory set and requires no
adjustment.
3 - After a 15-second prepurge, the hot surface ignitor
energizes.
4 - After a 20-second ignitor warm-up period, the gas
valve solenoid opens. A 4-second trial for ignition
period begins.”
5 - Gas is ignited, ame sensor proves the ame, and
the combustion process continues.
6 - If ame is not detected after rst ignition trial, the
ignition control will repeat steps 3 and 4 four
more times before locking out the gas valve
(“WATCHGUARD” ame failure mode). The ignition
control will then automatically repeat steps 1 through
6 after 60 minutes. To interrupt the 60-minute
“WATCHGUARD” period, move thermostat from
“Heat” to “OFF” then back to “Heat”. Heating
sequence then restarts at step 1.