Service Guide
SERVICING
42
A ame sensing device is used in conjunction with the ignition
control module to prove combustion. If proof of ame is not
present the control will de-energize the gas valve and “retry”
for ignition or lockout.
The following drawings illustrate from a bottom view, the
approximate distances for the ignitor and ame sensor to the
gas inshot burner. You will note they are in the main burner
stream, not in the carry over ports as shown in the following
gure.
S
R R SR R
S S
R SRS
RS
R S S RR
RS JR R
1. Disconnect the orange 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 1 to 4 micro-
amps. If the micro-amp reading is less than the minimum
specied, check for high resistance wiring connections,
sensor to burner gap, dirty flame 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.