Allied Air Enterprises WARM AIR GAS FURNACE 92G1UH - Manual (Page 42)

506724-01 Page 42 of 57 Issue 1108
Priming Condensate Trap
The condensate trap should be primed with water prior to
start-up to ensure proper condensate drainage. Either pour
10 fl. 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 fire 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 fire 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 sufficient water to
ensure proper condensate drain operation.
If you do not follow these instructions exactly, a fire or
explosion may result causing property damage, personal
injury or death.
WARNING
Gas Valve Operation (Figure 57)
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 gas valve switch to OFF. See Figure 57.
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
instructions. If you do not smell gas go to next step.
8. Move gas valve switch to ON. See Figure 57.
9. Replace the upper 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 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 upper access panel.
4. Move gas valve switch to OFF.
5. Replace the upper 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 filter dirty or plugged? Dirty or plugged filters 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, flame sensor proves the flame, and the
combustion process continues.
6. If flame is not detected after first ignition trial, the ignition
control will repeat steps 3 and 4 four more times before
locking out the gas valve. The ignition control will then
automatically repeat steps 1 through 6 after 60 minutes.
To interrupt the 60 minute period, move thermostat from
“Heat” to “OFF” then back to “Heat”. Heating sequence
then restarts at step 1.
MANIFOLD
PRESSURE
OUTLET
GAS VALVE SHOWN IN ON POSITION
INLET
PRESSURE
PORT
MANIFOLD
PRESSURE
ADJUSTMENT
SCREW
FIGURE 57
(UNDER CAP)