AVPTC Installation Manual

18
26 Air Handler Troubleshooting Matrix (continued)
Symptoms of Abnormal Operation
Diagnostic /
Status LED
Codes
Fault Description Possible Causes Corrective Actions
No Air Handler operation 
Circulator blower motor
senses a loss of rotor control
Circulator blower motor
senses high current
Abnormal motor loading, sudden
change in speed or torque, sudden
blockage of air handler air inlet or
outlet
Check filters, filter grills/registers, duct
system and air handler inlet/outlet f or
blockages
No Air Handler operation 
Circulator blower motor f ails to
start 10 consecutive times
Obstruction in circulator blower
housing
Seized Circulator blower motor
bearings
Failed circulator blower motor
Check circulator blower f or obstructions
Remove and repair/replace wheel/motor if
necessary
Check circulator blower motor shaf t rotation
and motor, replace motor if necessary
No Air Handler operation 
Circulator blower motor shuts
down for over or under voltage
condition
Circulator blower motor shuts
down due to over temperature
condition on power module
High or low AC line voltage to air
handler
Hi gh amb ient temperatures
Check power to air handler
Verify l ine voltage is within the range
specified on the rating plate
No Air Handler operation 
Circulator blower motor does
not have enough inf ormation
to operate properly
Motor fails to start 40
consecutive times
Error with integrated control module
shared data
Verify control is populated with the correct
shared data
Air Handler operates at reduced
perf ormance or operates on low stage
when high stage is expected

Airflow is lower than
demanded
Blocked filters or restrictive
ductwork
Undersized ductwork
Check f ilters for blockage, clean f ilters or
remove obstruction
Check ductwork for blockage, remove
obstruction and verify all registers are fully
open
Verify ductwork is appropriately sized for
system, resize/replace ductwork if necessary