GPG16M Service Manual

SERVICING

Flame

Sensor

Flame Sensor

2. Connect a microamp meter in series with this wire and

terminal FS.

3. Be sure the negative side of the meter is to the wire and

the positive of the meter is to terminal FS.

4. Turn on Power.

WARNING

Line Voltage now present.

5. With Power ON, Place the unit into a heating cycle.

6. As soon as flame is established a microamp reading

should be evident once proof of flame (microamp reading)

is established, the hot surface ignitor will be de-ener-

gized.

7. The nominal microamp reading is 4 microamps.

8. If the microamp current is less than 0.5 microamp the

control will lockout and flash a code of 1 flash after

attempting to reestablish flame sense.

9. If the microamp reading is less than the minimum speci-

fied, check for high resistance wiring connections, the

distance (3/16") between the sensor and burner, flame

sensor connections, dirty flame sensor or poor ground-

ing.

10. If no reading, check for continuity on all components and

if good - replace ignition control module.

NOTE: Contaminated fuel or combustion air can create a

nearly invisible coating on the flame sensor. This coating

works as an insulator causing a loss in the flame sense

signal. If this situation occurs the flame sensor must be

cleaned with steel wool. Do not use sand paper, the silicone

in sand paper will further contaminate the sensor.