Goodman ACS series Service Instructions Manual page 87

SYSTEM OPERATION
T
ROUBLESHOOTING
Associated
Symptoms of Abnormal
Operation
• Circulator blower runs
continuously. No furnace
operation.
• Integrated control module
diagnostic LED is flashing
FOUR (4) flashes.
• Induced draft blower
and circulator blower
runs continuously. No
furnace operation.
• Integrated control
module diagnostic LED is
flashing FIVE (5) flashes.
• Furnace fails to operate.
• Integrated control module
diagnostic LED is flashing
SIX (6) flashes.
• Normal furnace
operation.
• Integrated control
module diagnostic LED
is flashing SEVEN (7)
flashes.
• Furnace not operating.
• Integrated control
module diagnostic LED
is flashing EIGHT (8)
flashes.
• Integrated control module
diagnostic LED is flashing
continuously.
CONTINUOUS
On Steady
• LED is steady on
LED Flash codes will cease if power to the control module is interrupted through the disconnect or door switch.
2
8 Flases - applies to AMS8/ADS8 Models only (Silicon Nitride Models Only)
3
Integrated circuit boards on new furnace models AMH, GMH, GCH, GMS, GDS, GHS, GKS hold last 5 faults for service reference.
5
C
HART
Fault
LED
Description(s)
Code (2)(5)
• Primary limit
4 circuit is
open.
4 FLASHES
• Flame sensed
with no call
5
for heat.
5 FLASHES
• Rollout limit
open.
6
6 FLASHES
• Flame sense
microamp signal is
7
low.
7 FLASHES
• Problem with
8
igniter ciruit.
3
8 FLASHES
• Polarity of 115 volt
C
or 24 volt power
is reversed.
FLASHING
• Normal operation.
AMH8, AMS8, ADS8, DDS8, DMS8, DHS8,
GME8, GMH8, GMS8, GDH8, GDS8, GHS8
Possible Causes
• Check filters and
• Insufficient conditioned
air over the heat
exchanger. Blocked
filters, restrictive
• Check circulator blower
ductwork, improper
circulator blower speed,
or failed circulator
blower.
• Short to ground in flame
sense circuit.
• Lingering burner flame.
• Slow closing gas valve.
• Flame rollout.
• Misaligned burners,
blocked flue and/or air
inlet pipe, or failed
induced draft blower.
• Loose or improperly
connected wiring.
• Flame sensor is coated/ • Sand flame sensor is
oxidized.
• Flame sensor incor- • Inspect for proper
rectly positioned in
burner flame.
• Check inlet air piping for
• Lazy burner flame due
to improper gas
pressure or combustion
• Compare current gas
air.
• Check and correct
• Improperly connected
igniter.
• Bad igniter.
• Poor unit ground.
• Replace Bad igniter.
• Check and correct
• Polarity of 115 volt AC
power to furnace or
integrated control module
is reversed.
• Wires to 24 volt side of
transformer are reversed.
• Poor unit ground.
• Normal operation.
Corrective Action Cautions and Notes
• See Product
ductwork for blockage.
Data Bulletin for
Clean filters or remove
allowable rise
obstruction.
range and
proper circulator
speed.
speed and perfor-
mance. Correct speed
• Turn power OFF
or replace blower if
prior to repair.
necessary.
• Correct short at flame
• Turn power
sensor or in flame
OFF prior to
sensor wiring.
repair.
• Check for lingering
flame.
• Verify proper operation
of gas valve.
• Check burners for
• See "Vent/Flue
proper alignment.
Pipe" section for
piping details.
• Check flue and air inlet
piping for blockage,
proper length, elbows,
and termination.
• Replace induced
Correct as necessary.
draft blower
with proper
• Check induced draft
replacement
blower for proper
part.
performance. Replace,
if necessary.
• Tighten or correct
wiring connection.
• Turn power OFF
coated/oxidized. prior to repair.
• Clean flame
sensor alignment.
sensor with
steel wool.
blockage, proper length, • See "Vent/Flue
elbows, and termination.
Pipe" section for
piping details.
pressure to rating plate • See rating plate
info. Adjust as needed.
for proper gas
pressure.
• Turn power OFF
wiring from inte-
prior to repair.
grated control module
• Replace igniter
to igniter.
with proper
replacement
part.
unit ground wiring.
• Review wiring diagram
• Turn power OFF
to correct polarity.
prior to repair.
• Reverse wires
connected to 24 volt
side of transformer.
• Verify proper ground.
Correct if necessary.
• Check and correct
wiring if necessary.
• Normal operation.
• None.
87