7
Economizer Troubleshooting
LEGEND
PROBLEM
POSSIBLE CAUSE
REMEDY
Damper does not move
Indoor Fan is off
Check proper thermostat connection
Unit is not configured for continuous fan
operation and the thermostat is not calling for
heating or cooling
Unit is in Unoccupied mode and there is no
call for heating or cooling
Blown fuse (FU1, FU2)
Tripped circuit breaker (CB1, CB2, CB3)
No power to the unit
Unit is off via CCN command
Fan feedback is open and should be closed,
check for Fan Feedback alarm T409
Actuator is unplugged at motor or at
economizer board
Check wiring connections
Unit is not configured for economizer
Configure unit for economizer per the
instructions
Outdoor air temperature is above economizer
high temperature lockout
Adjust the high temperature lockout setting
if it is incorrect, otherwise, economizer is
operating correctly
Outdoor air temperature is below economizer
low temperature lockout
Adjust the low temperature lockout setting
if it is incorrect, otherwise, economizer is
operating correctly
Communication loss to economizer board
Check wiring connections
Damper is jammed
Identify the obstruction and safely remove
Economizer operation is limited
to minimum position
Minimum position is set incorrectly
Adjust minimum position setting
Outdoor-air temperature is above economizer
high temperature lockout
Adjust the high temperature lockout setting
if it is incorrect, otherwise, economizer is
operating correctly
Outdoor-air temperature is below economizer
low temperature lockout
Adjust the low temperature lockout setting
if it is incorrect, otherwise, economizer is
operating correctly
Outdoor-air thermistor is faulty
Replace outdoor air thermistor
Low suction pressure problem with a compressor
Economizer is operating correctly, identify
compressor problem
Economizer position is less
than minimum position
IAQ is controlling minimum damper position
Adjust the IAQ settings if incorrect,
otherwise the economizer is operating correctly
Unit is in Unoccupied mode
Adjust unit occupied schedule if incorrect,
otherwise, economizer is operating correctly
Economizer does not return
to minimum position
Unit is operating under free cooling
Economizer is operating correctly
Damper does not close on
power loss
Damper is jammed
Identify the obstruction and safely remove
CCN —
Carrier Comfort Network
IAQ
—
Indoor Air Quality
