Installation guide
12
Table 1. Interpreting the Diagnostic LEDS
Status LED
Status LED
Description
Status LED Troubleshooting Information
POWER
(Green LED)
Module has power Supply voltage is present at module terminals
TRIP
(Red LED)
Thermostat demand
signal Y is present,
but compressor is not
running
• Compressorprotectorisopen
• Checkforhighheadpressure
• Checkcompressorsupplyvoltage
• Outdoorunitpowerdisconnectisopen
• Compressorcircuitbreakerorfuse(s)isopen
• Brokenwireorconnectorisnotmakingcontact
• Lowpressureswitchopenifpresentinsystem
• Compressorcontactorhasfailedopen
ALERT
Flash Code 1
(Yellow LED)
Long Run Time
Compressor is running
extremely long run
cycles
•Lowrefrigerantcharge
•Evaporatorblowerisnotrunning
•Evaporatorcoilisfrozen
•Faultymeteringdevice
•Condensercoilisdirty
•Liquidlinerestriction(lterdrierblockedifpresentinsystem)
•Thermostatismalfunctioning
•ComfortAlertfailure
ALERT
Flash Code 2
(Yellow LED)
System Pressure Trip
•Highheadpressure
Discharge or suction •Condensercoilpooraircirculation(dirty,blocked,damaged)
Pressure out of limits •Condenserfanisnotrunning
Compressor overloaded
•Returnairducthassubstantialleakage
•Iflowpressureswitchpresentin system,checkFlashCode 1
information
ALERT
Flash Code 3
(Yellow LED)
Short Cycling /
Compressor is running
only briefly
•Thermostatdemandsignalisintermittent
•Lowlinevoltage(contactutilityifvoltageatdisconnectislow)
•Excessiveliquidrefrigerantincompressor
•Compressorbearingsareseized
ALERT
Flash Code 4
(Yellow LED)
Locked Rotor
•Runcapacitorhasfailed
•Lowlinevoltage(contactutitlityifvoltageatdisconnectislow)
•Checkwiringconnections
•Excessiveliquidrefrigerantincompressor
•Compressorbearingsareseized
•Measurecompressoroillevel
ALERT
Flash Code 5
(Yellow LED)
Open Circuit
•Outdoorunitpowerdisconnectisopen
•Compressorcircuitbreakerorfuse(s)isopen
•Compressorcontactorhasfailedopen
•Opencircuitincompressorsupplywiringorconnections
•Unusually long compressor protector reset timedueto extreme
ambient temperature
•Compressorwindingsaredamaged
ALERT
Flash Code 6
(Yellow LED)
Open Start Circuit
Current only in run
circuit
•Runcapacitorhasfailed
•Opencircuitincompressorstartwiringorconnections
•Compressorstartwindingisdamaged
ALERT
Flash Code 7
(Yellow LED)
Open run circuit
Current only in start
circuit
•Opencircuitincompressorrunwiringorconnections
•Compressorrunwindingisdamaged
ALERT
Flash Code 8
(Yellow LED)
Welded Contactor
Compressor always
runs
•Compressorcontactorhasfailedclosed
•Thermostatdemandsignalnotconnectedtomodule
ALERT
Flash Code 9
(Yellow LED)
Low Voltage
Control circuit <
17VAC
•Controlcircuittransformerisoverloaded
•Lowlinevoltage(contactutilityifvoltageatdisconnectislow)
•Checkwiringconnections
* Flash code number corresponds to a number of LED flashes, followed by a pause and then repeated. Trip and alert LED’s
flashing at same time means control circuit voltage is too low for operation.










