August 1999
6.1-2
2
Voltage Checks
Component
Testing
Control M
Module TTerminal D
Designators aand VVoltages
(Part #
#120-0
08027)
IGN
120 V.A.C. from module to igniter
L
120 V.A.C. power supply to module
GND
Control module ground
FP
24 V.A.C. from module to flame sensor
TH
24 V.A.C. from transformer through air proving switch,
to high limit switch, and finally to control module
TR
Neutral return for transformer
MV
Neutral return for control valve
MV
24 V.A.C. to gas control valve
Control M
Module
Part #
#120-0
08027
AATTTTEEN
NTTIIO
ON
N
The control module has three diagnostic light patterns:
-- No Light:
Normal operation.
-- Steady On Light:
Fault is internal to module. Replace module.
-- Flashing Light:
Problem is within other heater components or wiring. Refer to wiring diagram for Model 284/285
heaters within Section 7 for assistance in determining failure.
