Goodman GMVM - Page 78

78
Troubleshooting
ComfortNetThermostat
Only
Symptoms of Abnormal Operation
(Non-communicating & ComfortNet™
Thermostat)
Diagnostic/Status
LED Codes
Fault Description
Message Code
Possible Causes Corrective Actions Notes & Cautions
x Operation different than expected or no
operation.
x Integrated control module LED display
provides d
4
error code.
x ComfortNet thermostat “Call for Service”
icon illuminated.
x ComfortNet thermostat scrolls “Check
Furnace” message.
d4
x Invalid memory card
data.
INVALID MC
DATA
d4
x Shared data set on memory card
has been rejected by integrated control module
x Verify shared data set is correct
for the specific model. Re- populate data using correct memory card if required.
x Turn power OFF prior to
repair
x Use memory card for the
specific model.
x Insert memory card
BEFORE turning power ON. Memory card may be removed after data is loaded.
x Turn power OFF before
removing memory card.
x Error code will be cleared
once data is loaded.
x Furnace fails to operate. x Integrated control module LED display
provides b
0
error code.
x ComfortNet thermostat “Call for Service”
icon illuminated.
x ComfortNet thermostat scrolls “Check
Furnace” message.
b0
x Circulator blower motor
is not running when it should be running.
MOTOR NOT
RUN
b0
x Loose wiring connection at
circulator motor power leads or circulator motor power leads disconnected.
x Open circuit in inductor or loose
wiring connection at inductor (3/4 Hp and 1 Hp models only).
x Failed circulator blower motor.
x Tighten or correct wiring
connection.
x Verify continuous circuit
through inductor. Replace if open or short circuit.
x Check circulator blower motor.
Replace if necessary.
x Turn power OFF prior to
repair
x Replace inductor with
correct replacement part.
x Replace circulator motor
with correct replacement part.
x Furnace fails to operate. x Integrated control module LED display
provides b
1
error code.
x ComfortNet thermostat “Call for Service”
icon illuminated.
x ComfortNet thermostat scrolls “Check
Furnace” message.
b1
x Integrated control
module has lost communications with circulator blower motor.
MOTOR
COMM
b1
x Loose wiring connection at
circulator motor control leads.
x Failed circulator blower motor. x Failed integrated control module.
x Tighten or correct wiring
connection.
x Check blower motor with UTT-
01 Emerson tester
x Check integrated control
module. Replace if necessary.
x Turn power OFF prior to
repair
x Replace circulator motor
with correct replacement part.
x Replace integrated control
module with correct replacement part.
x Furnace fails to operate. x Integrated control module LED display
provides b
2
error code.
x ComfortNet thermostat “Call for Service”
icon illuminated.
x ComfortNet thermostat scrolls “Check
Furnace” message.
b2
x Circulator blower motor
horse power in shared data set does not match circulator blower motor horse power.
MOTOR
MISMATCH
b2
x Incorrect circulator blower motor
in furnace.
x Incorrect shared data set in
integrated control module.
x Verify circulator blower motor
horse power is the same specified for the specific furnace model. Replace if necessary.
x Verify shared data set is correct
for the specific model. Re- populate data using correct memory card if required.
x Turn power OFF prior to
repair
x Replace motor with
correct replacement part.
x Use memory card for the
specific model
x Insert memory card
BEFORE turning power ON. Memory card may be removed after data is loaded.
x Turn power OFF before
removing memory card.
x Error code will be cleared
once shared data and motor horse power match.
x Furnace operates at reduced performance. x Airflow delivered is less than expected. x Integrated control module LED display
provides b
3
error code.
b3
x Circulator blower motor
is operating in a power, temperature, or speed limiting condition.
MOTOR
LIMITS
b3
x Blocked filters. x Restrictive ductwork. x Undersized ductwork. x High ambient temperatures.
x Check filters for blockage.
Clean filters or remove obstruction.
x Check ductwork for blockage.
Remove obstruction. Verify all registers are fully open.
x Verify ductwork is appropriately
sized for system. Resize/replace ductwork if necessary.
x See "Product Description" and
"Location Requirements & Considerations" for furnace installation requirements.
x Turn power OFF prior to
repair.