Installation Guide

41


due to an excessive
number of ignition

1
.
Locate and correct gas
interruption.
Check front cover
pressure switch oper-


Correct if necessary.
Replace or realign
igniter.

signal. Sand sensor
if coated and/or oxi-
dized.

for blockage, proper
length, elbows, and
termination.

draft blower perfor-
mance.
• Turn power

repair.
• Igniter is
fragile, handle
with care.

sensor with
emery cloth.

-
tion for piping
details.

• Integrated control
module diagnostic is

1


Cause may be no gas to
burners, front cover pres-
sure switch stuck open, bad
igniter or igniter alignment,
-
ed/oxidized or improperly

-
lishment. Cause may be
interrupted gas supply, lazy

gas pressure or restriction


pressure switch opening,
or improper induced draft
blower performance.
Pressure switch
circuit is closed.
Induced draft
blower 
operating.

prior to repair.
• Replace pressure
switch with prop-
er replacement
part.

• Integrated control
module diagnostic is

2

Induced draft blower
pressure switch contacts
sticking.
Shorts in pressure switch
circuit.
Pressure switch hose
blocked, pinched or con-
nected improperly.

air pipe, blocked drain
system, or weak induced
draft blower.
Incorrect pressure switch
setpoint or malfunctioning
switch contacts.
Loose or improperly con-
nected wiring.
Pressure switch
circuit not closed.
Induced draft blow-
er operating.
Induced draft blower runs
continuously with no fur-
ther furnace operation.
Integrated control module
diagnostic 

• Turn power

repair.
• Replace pres-
sure switch
with proper
replacement
part.




• Normal Operation
• Normal Operation
• None
• Normal Operation
No 115 volt power
to furnace, or no
24 volt power to
integrated control
module.
Blown fuse or circuit
breaker.
• Integrated control
module has an inter-
nal fault.
Manual disconnect switch

24 volt wires improperly
connected or loose.
Blown fuse or circuit
breaker.
Integrated control module
has an internal fault.
Assure 115 and 24 volt
power to furnace inte-
grated control module.
Check integrated con-

Replace if necessary.
Check for possible
shorts in 115 and 24
volt circuits. Repair as
necessary.
Replace bad integrated
control module.

prior to repair.
• Replace
integrated
control module
fuse with 3A auto-
motive fuse.
• Read precautions
in “Electrostatic

of manual.

• Integrated control
module diagnostic 
provides .
NONE






• Replace induced
draft blower pressure
switch.
• Repair short.
Inspect pressure switch
hose. Repair, if neces-
sary,

air piping for blockage,
proper length, elbows,
and termination. Check
drain system. Correct as
necessary.
Correct pressure switch
setpoint or contact
motion.
Tighten or correct wiring
connection.
ON
CONTINUOUS
ON
Integrated control module will automatically attempt to reset from lockout after one hour.

2
3
