Instructions / Assembly

26
25 Troubleshooting (Sheet 3 of 4)
ComfortNet™
Thermostat Only
Symptoms of Abnormal Operation
(Legacy & ComfortNet™ Thermostat)
7-Segment LED
Codes
Characters
Will Alternate
Fault Description
Message Code
Possible Causes
Corrective Actions
Notes & Cautions
x Air handler blower fails to operate. x Integrated control module LED display
provides indicated error code.
x ComfortNet™ thermostat “Call for
Service” icon illuminated.
x ComfortNet™ thermostat scrolls
“Check Air Handler” 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 Failed circulator blower motor.
x Tighten or correct wiring
connection.
x Check circulator blower
motor. Replace if necessary.
x Turn power OFF prior to
repair
x Replace circulator motor
with correct replacement part.
x Air handler blower fails to operate. x Integrated control module LED display
provides indicated error code.
x ComfortNet™ thermostat “Call for
Service” icon illuminated.
x ComfortNet™ thermostat scrolls
“Check Air Handler” 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 circulator blower
motor. Replace if necessary.
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 Air handler blower fails to operate. x Integrated control module LED display
provides indicated error code.
x ComfortNet™ thermostat “Call for
Service” icon illuminated.
x ComfortNet™ thermostat scrolls
“Check Air Handler” 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 air handler blower.
x Incorrect shared data set in
integrated control module.
x Verify circulator blower motor
horse power is the same specified for the specific air handler blower model. Replace is 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 Error code will be
cleared once shared data and motor horse power match.
x Turn power off before
removing memory card
x Air handler blower operates at reduced
performance.
x Airflow delivered is less than expected. x Integrated control module LED display
provides b3 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 "Installation Instructions"
for installation requirements.
x Turn power OFF prior to
repair.
x Air handler blower fails to operate. x Integrated control module LED display
provides indicated error code.
x ComfortNet™ thermostat “Call for
Service” icon illuminated.
x ComfortNet™ thermostat scrolls
“Check Air Handler” message.
b4
x Circulator blower
motor senses a loss rotor control.
x Circulator blower
motor senses high current.
MOTOR
TRIPS
b4
x Abnormal motor loading,
sudden change in speed or torque, sudden blockage of air handler blower/coil air inlet or outlet.
x High loading conditions,
blocked filters, very restrictive ductwork, blockage of air handler blower/coil air inlet or outlet.
x Check filters, filter
grills/registers, duct system, and air handler blower/coil air inlet/outlet for blockages.
x Turn power OFF prior to
repair.