Troubleshooting - Maytag Amana GMES9 Series Service Instructions Manual

TROUBLESHOOTING

Symptoms of Abnormal
Operation
• Furnace fails to oper-
ate.
• Integrated control
module diagnostic LED
provides no signal.
• LED is Steady On.
• Furnace fails to oper-
ate.
• Integrated control mod-
ule diagnostic LED is
flashing ONE (1) flash.
• Furnace fails to operate.
• Integrated control module
diagnostic LED is flashing
TWO (2) flashes.
• Induced draft blower
runs continuously with
no further furnace oper-
ation.
• Integrated control
module diagnostic LED
is flashing THREE (3)
flashes.
1 Integrated control module will automatically attempt to reset from lockout after one hour.
2 LED Flash code will cease if power to the control module is interrupted through the disconnect or door switch.
Associated
Associated Fault Descrip-
Fault Descrip-
tion(s)
LED Code
2
LED Code
2
tion(s)
• No 115 volt power
NONE
to furnace, or no
24 volt power to
integrated control
module.
• Blown fuse or circuit
breaker.
• Integrated control
module has an
internal fault.
• Normal Operation
ON
CONTINUOUS
ON
• Furnace lockout
due to an excessive
1
number of ignition
"retries" (3 total)
1 FLASH
• Pressure switch
circuit is closed.
2
• Induced draft
blower is not
2 FLASHES
operating.
• Pressure switch
circuit not closed.
3
• Induced draft blow-
er is operating.
3 FLASHES
Possible Causes
Possible Causes
• Manual disconnect
switch OFF, door switch
open, or 24 volt wires
improperly connected or
loose.
• Blown fuse or circuit
breaker.
• Integrated control mod-
ule has an internal fault.
• Normal Operation
• Failure to establish flame.
Cause may be no gas
to burners, front cover
pressure switch stuck
.
1
open, bad igniter or igniter
alignment, improper ori-
fices, or coated/oxidized
or improperly connected
flame sensor.
• Loss of flame after estab-
lishment. Cause may be
interrupted gas supply, lazy
burner flames (improper
gas pressure or restriction
in flue and/or combustion
air piping), front cover
pressure switch opening,
or improper induced draft
blower performance.
• Induced draft blower
pressure switch contacts
sticking.
• Shorts in pressure switch
circuit.
• Pressure switch hose
blocked, pinched or con-
nected improperly.
• Blocked flue and/or inlet
air pipe, blocked drain
system, or weak induced
draft blower.
• Incorrect pressure switch
setpoint or malfunctioning
switch contacts.
• Loose or improperly con-
nected wiring.
PCBBF145
Corrective Action Cautions and
• Assure 115 and 24 volt • Turn power OFF
power to furnace integrated prior to repair.
control module.
• Replace integrated
• Check integrated control control module
module fuse (3A). Replace fuse with 3A auto-
if necessary. motive fuse.
• Check for possible shorts • Read precautions
in 115 and 24 volt circuits. in "Electrostatic
Repair as necessary. Discharge" sec-
tion of manual.
• Replace bad integrated
control module.
• None
• Normal Operation
• Locate and correct gas
• Turn power
interruption.
OFF prior to
repair.
• Check front cover pres-
sure switch operation
• Igniter is
(hose, wiring, contact
fragile, handle
operation). Correct if
with care.
necessary.
• Clean flame
• Replace or realign ignit-
sensor.
er.
• See "Vent/
• Check flame sense
Flue Pipe"
signal. Clean sensor if
section for
coated and/or oxidized.
piping details.
• Check flue piping for
blockage, proper length,
elbows, and termination.
• Verify proper induced
draft blower perfor-
mance.
• Turn power OFF
• Replace induced
prior to repair.
draft blower pressure
• Replace pressure
switch.
switch with proper
• Repair short.
replacement part.
• Inspect pressure
• Turn power
switch hose. Repair, if
OFF prior to
necessary,
repair.
• Inspect flue and/
• Replace
or inlet air piping for
pressure
blockage, proper
switch with
length, elbows, and
proper
termination. Check
replacement
drain system. Correct
part.
as necessary.
• Correct pressure
switch setpoint or
contact motion.
• Tighten or correct
wiring connection.
Notes
43