Lennox Merit ML296UH110XV60C - Unit Start-Up and Operation; Priming Condensate Trap

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Unit Start-Up
FOR YOUR SAFETY READ BEFORE OPERATING
WARNING
Do not use this furnace if any part has been underwater.
A ood-damaged furnace is extremely dangerous.
Attempts to use the furnace can result in re or explosion.
Immediately call a qualied service technician to inspect
the furnace and to replace all gas controls, control
system parts, and electrical parts that have been wet or
to replace the furnace, if deemed necessary.
WARNING
Danger of explosion. Can cause injury or
product or property damage. If overheating
occurs or if gas supply fails to shut o󰀨, shut
o󰀨 the manual gas valve to the appliance
before shutting o󰀨 electrical supply.
CAUTION
Before attempting to perform any service or maintenance,
turn the electrical power to unit OFF at disconnect switch.
BEFORE LIGHTING the unit, smell all around the furnace
area for gas. Be sure to smell next to the oor because
some gas is heavier than air and will settle on the oor.
The gas valve on the ML296UHV is equipped with a gas
control switch (lever). Use only your hand to move switch.
Never use tools. If the switch will not move by hand, do
not try to repair it. Force or attempted repair may result in
a re or explosion.
Placing the furnace into operation:
ML296UHV units are equipped with an automatic hot
surface 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 these units.
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
su󰀩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 63)
1 - STOP! Read the safety information at the beginning
of this section.
2 - Set the thermostat to the lowest setting.
3 - Turn o󰀨 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 63.
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 63.
GAS VALVE SHOWN IN ON POSITION
INLET PRESSURE POST
HIGH FIRE ADJUSTMENT
SCREW
(under cap)
MANIFOLD
PRESSURE TAP
WHITE RODGERS GAS VALVE
FIGURE 63
9 - Replace the access panel.
10- Turn on all electrical power 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 O󰀨 Gas to Unit” and call your
service technician or gas supplier.
Turning O󰀨 Gas to Unit
1 - Set the thermostat to the lowest setting.
2 - Turn o󰀨 all electrical power to the unit if service is to
be performed.
3 - Remove the access panel.