22
YES
CAUTION
!
label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation. VERiFY PROP-
ER OPERATiON AFTER SERViCiNg!
Section 3... the “igNiTiON” lED
“System Sentinel” Troubleshooting guide
is the Blower Operating?
1. Remove ignition Cable and check for
good continuity, replace if necessary.
2. Check ignitor Electrode(s) gap for proper
spacing (1/8” to 5/32”). Correct if neces-
sary.
3. Examine Ceramic insulator on Pilot
Assembly for cracks. Replace if cracks
are evident.
if all of the above components check okay,
replace ignition Control module.
is 24 VAC present between the
gray ground wire and the Red
24 V wire connected to the igni-
tion Control module?
is there 24 VAC present
between the common and
Normally open terminal of
pressure switch 1?
is Spark ignitor operating?
(Can sparking be heard?)
The System Sentinel Panel is
defective and must be replaced.
Wiring harness is defec-
tive and must be replaced.
Check Con-
tinuity of the
Red wire from
the ignition
module to
the Pressure
Switch.
is continuity
good?
The Thermostat has called for
heat, the Blower is running, and
24 VAC power is being supplied to
the ignition Control module and
the ignition sequence will begin.
YES
YES
YES
YES
NO
NO
NO
NO
NO
is the ignition lED illuminated?
is there 120 VAC
across Black wire
and White wire of
blower?
YES
NO
is there 120
VAC between
the black wire at
the relay and the
white wire on the
transformer?
NO
YES
Blower is
d e f e c t i v e
and must be
replaced.
Check continuity
of black wire from
relay to blower
motor and white
wire to motor.
is continuity
good?
Check continuity
of black wire to
relay.
is continuity
good?
YES
C h e c k
wire con-
nections.
NO
W i r e
is defec-
tive and
must be
replaced.
is there 120 VAC between the
black wire on the relay (power
going to blower) and the white
wire of the transformer?
is 24
VAC present
across coil
of relay?
YES
R e l a y i s
d e f e c t i v e
and must be
replaced.
NO
YES
Review pressure switch circuit
on this page.
Recheck all connections,
should have power at blower motor.
YES
NO
Check con-
t i nu i t y o f
yellow wires
to pressure
s w i t c h e s
and between
switches.
is continuity
good?
Pressure Switch
is defective and
must be replaced.
P o w e r
should be
at 24 VAC
of ignition
module.
NO
YES
YES
NO
