Goodman ACS series Service Instructions Manual page 90

SYSTEM OPERATION
T
ROUBLESHOOTING
Associated
Symptoms of Abnormal
Operation
LED Code
• Furnace fails to operate.
• Integrated control
module diagnostic LED
provides no signal.
• LED is steady ON.
CONTINUOUS
• Furnace fails to operate.
• Integrated control
module diagnostic LED
is flashing ONE (1)
1 FLASH
flash.
• Furnace fails to operate.
• Integrated control
module diagnostic LED
is flashing TWO (2)
2 FLASHES
flashes.
• Induced draft blower
runs continuously with
no further furnace
operation.
3 FLASHES
• 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 control module is interrupted throught the disconnect or door switch.
4
Applies to ADV8, AMV8, GMV8 only.
90
C
HART
Fault
2
Description(s)
NONE • No 115 volt power
to furnace, or no 24
volt power to
integrated control
module.
• Blown fuse or
circuit breaker.
• Intergrated contol
module has an
internal fault
• Normal operation.
ON
ON
• Furnace lockout
1 due to an
excessive
number of
ignition "retries"
(3 total) 1 .
• Auxiliary limit
open
• Low stage
pressure switch
2
circuit is closed.
• Induced draft
blower is not
operating.
• Pressure
3
switch circuit
not closed.
• Induced draft
blower is
operating.
ADV8, AMV8, ACV9, AMV9, GMV8, GCV9, GMV9
Possible Causes
• Manual disconnect switch
OFF, door switch open, or
24 volt wires improperly
connected or loose.
• Blown fuse or circuit
breaker.
• Intergrated contol module
has an internal fault
• Normal operation.
• Failure to establish flame.
Cause may be no gas to
burners, bad igniter or
igniter alignment, improper
orifices, or coated/oxidized
or improperly connected
flame sensor.
• Loss of flame after
establishment. Cause may
be interrupted gas supply,
lazy burner flames
(improper gas pressure or
restriction in flue or
improper induced draft
blower performance.
• Insufficient conditioned air
over the heat exchanger.
Blocked filters, restrictive
ductwork, improper
circulator blower speed, or
failed circulator blower.
• Induced draft blower
pressure switch contacts
sticking.
• Shorts in pressure switch
circuit.
• Pressure switch hose
blocked, pinched or
connected improperly.
• Blocked flue or weak
induced draft blower.
• Incorrect pressure switch
setpoint or malfunctioning
switch contacts.
• Loose or improperly
connected wiring.
Corrective Action Cautions and Notes
• Assure 115 and 24 volt • Turn power OFF
power to furnace
integrated control
• Replace integrated
module.
• Check integrated control
module fuse (3A).
Replace if necessary.
• Read precautions
• Check for possible
shorts in 115 and 24
volt circuits. Repair as
necessary.
• Replace bad intergrated
control module.
• Normal operation.
• None.
• Turn power OFF
• Locate and correct gas
interruption.
• Replace or realign
• Igniter is fragile,
igniter.
• Check flame sense
• Sand flame sensor
signal. Sand sensor if
coated and/or oxidized.
• See "Combustion
• Check flue piping for
blockage, proper length,
elbows, and termination.
• Verify proper induced
draft blower perfor-
mance.
• Check circulator blower
• See Product Data
speed and performance.
Correct speed or
replace blower if
necessary.
• Replace induced draft • Turn power OFF
blower pressure
switch.
• Replace pressure
• Repair short.
• Inspect pressure • Turn power OFF
switch hose. Repair, if prior to repair.
necessary,
• See "Combustion
• Inspect flue for
and Ventilation Air
blockage, proper
Requirements"
length, elbows, and
and "Category I
termination.
Venting (Vertical
Venting)" section
• Correct pressure
for details.
switch setpoint or
• Replace pressure
contact motion.
switch with
• Tighten or correct
proper replace-
wiring connection.
ment part.
prior to repair.
control module
fuse with 3A
automotive fuse.
in "Electrostatic
Discharge" section
of manual.
prior to repair.
handle with care.
with emery cloth.
and Ventilation Air
Requirements" and
"Category I
Venting (Vertical
Venting)" section
for details.
Bulletin for
allowable rise
range and proper
circulator speed.
prior to repair.
switch with proper
replacement part.