Goodman ACS series Service Instructions Manual page 88

SYSTEM OPERATION
T
ROUBLESHOOTING
Associated
Symptoms of Abnormal
Operation
• 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) time.
1 FLASH
• Furnace fails to operate.
• Integrated control
module diagnostic LED
is flashing TWO (2)
times.
• Induced draft blower
runs continuously with
no further furnace
operation.
3 FLASHES
• Integrated control
module diagnostic LED
is flashing THREE (3)
times.
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.
88
C
HART
lt Description(s)
Fault
Description(s)
LED Code 2
• 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
ON
• Furnace lockout
due to an exces-
1
sive number of
ignition "retries" (3
total) 1 .
• "Recycles" are
infinite.
• Pressure switch
circuit is closed.
2
• Induced draft
blower is not
2 FLASHES
operating.
• Pressure switch
3
circuit not closed.
• Induced draft
blower is
operating.
AMS9, ACS9, DMS9, DCS9, GMS9,
GCS9, GKS9, AMS95, GMS95
Possible Causes
• Assure 115 and 24 volt
• Manual disconnect
switch OFF, door switch
open, or 24 volt wires
improperly connected or • Check integrated control
loose.
• Blown fuse or circuit
• Check for possible
breaker.
• Integrated control
module has internal
fault.
• Replace bad integrated
• Normal operation.
• Failure to establish flame.
Cause may be no gas to
burners, front cover
pressure switch stuck
open, 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 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
connected 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
connected wiring.
Corrective Action
• Turn power OFF
prior to repair.
power to furnace
integrated control module.
• Replace integrated
control module
module fuse (3A).
fuse with 3A
Replace if necessary.
automotive fuse.
• Read precautions
shorts in 115 and 24 volt
in "Electrostatic
circuits. Repair as
Discharge"
necessary.
section of manual.
control module.
• Normal operation.
• None.
• Locate and correct gas
• Turn power
interruption.
OFF prior to
repair.
• Check front cover
pressure switch
operation (hose, wiring,
contact operation).
Correct if necessary.
• Replace or realign
• Igniter is
igniter.
fragile, handle
• Check flame sense
with care.
signal. Sand sensor if
• Sand flame
coated and/or oxidized.
sensor with
• Check flue piping for
emery cloth.
blockage, proper
• See "Vent/
length, elbows, and
Flue Pipe"
termination.
section for
• Verify proper induced
piping details.
draft blower perfor-
mance.
• Turn power OFF
• Replace induced draft
prior to repair.
blower pressure switch.
• Replace pressure
• Repair short.
switch with proper
replacement.
• Inspect pressure
• Turn power OFF
switch hose. Repair, if
necessary,
• Inspect flue and/or inlet
• Replace
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.
Cautions
and Notes
prior to repair.
pressure switch
with proper
replacement
part.