Proheat M125 - Manual (Page 58)

4-21 PROHEAT M-SERIES G-II PCM SERVICE MANUAL
f) Switch the PROHEAT on and observe for a spark. Spark will continue for
five seconds.
If the spark is OK, reinstall the burner head and review Fuel System
troubleshooting, page 4-5.
WARNING
Keep blower housing on to avoid
injury when Motor starts up.
NOTICE
All plugs/harnesses must be rein-
stalled into the G-II Proheat Control
Module (G-II PCM) before heater
goes back into service.
NOTICE
Leaving the Dual Mode Temperature
Sensor disconnected ensures that the
burner head will enter Cool Down
(Purge) mode and run for a maximum
of three minutes.
d) Disconnect the Ignition Module connector at the G-II PCM.
e) Check for contamination on the Flame Sensor. Clean if necessary using
electrical contact cleaner and a soft cloth.
f) Reconnect the power harness.
WARNING
To avoid the risk of shock and to
ensure that the PROHEAT does not
fire, disconnect the Ignition Module
connector at the G-II PCM.
Flame Sensor – Check:
a) Flame Sensor operation.
b) Combustion tube orientation.
Test Procedure – Flame Sensor circuit:
a) Disconnect all harnesses at the G-II PCM.
b) Disconnect the fuel supply line.
c) Loosen and back off the burner head mounting (2) bolts five to six turns
allowing enough room to rotate the burner head 15° counter-clockwise
and remove.
START: G-II PCM Flame
Sensor Circuit (1 Flash)
Figure 4-23: Burner Head Removal and Flame Sensor Location.
FLAME SENSOR PORT
MOUNTING EARS (2)
MOUNTING BOLTS (2)
TORQUE = SEE SECTION 1.3
COOLANT PUMP
SWITCH INPUT
DUAL MODE TEMP
SENSOR
POWER
FUEL INLET