SERVICING
23
1. Check for 120 volts from Line 1 (Hot) to Line 2 (Neutral)
at the ignition control. No voltage, check the door switch
connections and wire harness for continuity.
2. Check for 24 volts from W to C terminal on the ignition
control. No voltage. Check transformer, room thermostat,
and wiring.
If you have 24 volts coming o the transformer but receive
approximately 13 volts on the terminal board between (C)
and (R), check for blown fuse.
3. Check for 120 volts to the induced draft blower by
measuring voltage between Pin 4 & 5 (black & white wire
on 5 pin connector.)
4. If voltage is present in Steps 1 through 3 and the induced
draft blower is operating, check for 120 volts to the ignitor
during the preheat cycle.
5. After the ignitor warmup time, begin checking for 24 volts
to the gas valve. Voltage will be present for seven seconds
only if proof of ame has been established.
S
R R SR R
S S
R SRS
RS
R S S RR
RS JR R
1. Disconnect the yellow ame sensor wire from the sensor
2. Connect a micro-amp meter in series with this wire and
the sensor terminal.
3. Place the unit into a heating cycle.
RS
4. As soon as ame is established a micro-amp reading
should be evident once proof of flame (micro-amp
reading) is established, the hot surface ignitor will be de-
energized.
5. The Integrated Ignition controls will have 3-10 uAmps.
1-3 uAmps is considered low and will ash 1 amber light.
Anything below 1 uAmps and the unit will shut down. If
the micro-amp reading is less than the minimum specied,
check for high resistance wiring connections, sensor to
burner gap, dirty ame sensor, or poor grounding.
6. If absolutely no reading, check for continuity on all
components and if good - replace ignition control module.
Contaminated fuel or combustion air can create a
nearly invisible coating on the ame sensor. This coating
works as an insulator causing a loss in the ame sense signal.
If this situation occurs the ame sensor must be cleaned with
steel wool.
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