HVAC Error Codes
Find error codes for heating and cooling systems. Browse by device type below.
Error Codes
C1
Universal
HVAC System
HVAC error code C1 means the compressor failed to start within the expected time …
C4
Universal
HVAC System
HVAC error code C4 typically means the condensate drain float switch has …
C5
Universal
HVAC System
HVAC error code C5 indicates a problem with the indoor unit's swing motor or …
C6
Universal
HVAC System
C6 means your HVAC system has detected a fault with the outdoor unit's fan …
C7
Universal
HVAC System
Error C7 means the outdoor temperature sensor on your HVAC system has a problem. …
C8
Universal
HVAC System
Error C8 means the condensate drain sensor inside your HVAC unit has detected …
E0
Universal
HVAC System
HVAC error code E0 indicates a communication failure or general system fault.
On …
E1
Universal
HVAC System
E1 means the room temperature sensor in your air conditioner or heat pump has a …
E10
Universal
HVAC System
HVAC error code E10 means the system has detected a mismatch between the indoor …
E11
Universal
HVAC System
HVAC error code E11 typically indicates a communication error between the indoor …
E12
Universal
HVAC System
Error E12 means the refrigerant pressure inside your HVAC system is outside the …
E13
Universal
HVAC System
E13 on an HVAC system typically indicates a refrigerant pressure fault.
The …
E2
Universal
HVAC System
E2 means the coil temperature sensor (also called the evaporator or pipe sensor) …
E3
Universal
HVAC System
E3 means the low pressure protection switch has tripped in your HVAC system. …
E4
Universal
HVAC System
E4 means the compressor has triggered its overload protection and shut down.
The …
E5
Universal
HVAC System
E5 means the overcurrent protection has activated in your HVAC system.
The unit …
E6
Universal
HVAC System
E6 on an HVAC system means the indoor unit and outdoor unit are not …
E7
Universal
HVAC System
E7 means the outdoor fan motor in your HVAC system has failed or is not …
E8
Universal
HVAC System
E8 means the indoor fan motor — also called the blower motor — has a problem. …
E9
Universal
HVAC System
E9 means the outdoor coil temperature sensor has a problem.
This sensor monitors …
F0
Universal
HVAC System
HVAC error code F0 typically indicates a sensor initialization failure or a …
F1
Universal
HVAC System
F1 on an HVAC system typically means the ambient temperature sensor — sometimes …
F10
Universal
HVAC System
HVAC error code F10 means the indoor evaporator coil has frozen or iced over, …
F11
Universal
HVAC System
HVAC error code F11 typically indicates an outdoor fan motor fault.
The outdoor …
F12
Universal
HVAC System
Error F12 means the inverter control board inside your outdoor HVAC unit has …
F2
Universal
HVAC System
F2 on an HVAC system typically means there is a fault with the evaporator coil …
F3
Universal
HVAC System
HVAC error F3 indicates a condenser coil temperature sensor fault.
The sensor …
F4
Universal
HVAC System
HVAC error F4 indicates a discharge line temperature sensor fault.
The discharge …
F5
Universal
HVAC System
HVAC error F5 indicates a suction line temperature sensor fault.
The suction …
F6
Universal
HVAC System
F6 means the outdoor ambient temperature sensor is not working correctly.
This …
F7
Universal
HVAC System
F7 means the outdoor discharge temperature sensor has a fault.
The discharge …
F8
Universal
HVAC System
F8 means the compressor has reached a dangerously high temperature and shut …
F9
Universal
HVAC System
F9 means the IPM module — the Intelligent Power Module — has triggered its …
H1
Universal
HVAC System
HVAC code H1 means your heat pump has entered defrost mode.
This is a completely …
H10
Universal
HVAC System
HVAC error code H10 typically indicates a defrost failure or a heat pump defrost …
H2
Universal
HVAC System
H2 means the compressor is drawing more electrical current than it should.
The …
H3
Universal
HVAC System
H3 means the compressor's internal thermal overload protector has tripped.
Every …
H4
Universal
HVAC System
H4 means the HVAC system has detected an abnormal operating condition and has …
H5
Universal
HVAC System
H5 means the IPM module — the Intelligent Power Module — has failed or detected …
H6
Universal
HVAC System
HVAC error H6 means the indoor blower fan has stopped running or is running at …
H7
Universal
HVAC System
HVAC error code H7 means the system detected a problem with the outdoor …
H8
Universal
HVAC System
H8 means your HVAC system has detected a problem with the current (amperage) …
H9
Universal
HVAC System
H9 means your HVAC system has detected a fault with the outdoor ambient …
L1
Universal
HVAC System
HVAC error code L1 means the outdoor unit has detected an internal abnormality …
L2
Universal
HVAC System
L2 on an HVAC system typically indicates an outdoor unit current fault or power …
L5
Universal
HVAC System
L5 means the DC bus voltage inside the inverter circuit has dropped below a safe …
L9
Universal
HVAC System
HVAC error code L9 typically indicates a compressor overload or a capacity …
LC
Universal
HVAC System
HVAC error code LC typically means there is a drain blockage, float switch trip, …
P1
Universal
HVAC System
HVAC error code P1 means the system detected a problem with voltage or power …
P2
Universal
HVAC System
HVAC error code P2 usually means there is a high-pressure fault in the …
P3
Universal
HVAC System
HVAC error code P3 means the system detected dangerously high pressure on the …
P4
Universal
HVAC System
HVAC error code P4 typically indicates an inverter or compressor module fault. …
P5
Universal
HVAC System
HVAC error code P5 means the control board has lost communication with the …
P6
Universal
HVAC System
P6 means the Intelligent Power Module (IPM) inside your HVAC unit has triggered …
P7
Universal
HVAC System
HVAC error code P7 commonly indicates a power supply voltage problem or a DC bus …
P8
Universal
HVAC System
Error P8 means the IPM (Intelligent Power Module) inside your HVAC system has …
P9
Universal
HVAC System
P9 on an HVAC system typically indicates a compressor inverter module fault. …
U1
Universal
HVAC System
HVAC error code U1 means the system detected an overcurrent condition in the …
U2
Universal
HVAC System
U2 means your HVAC system has detected that the supply voltage is abnormal — …
U3
Universal
HVAC System
U3 indicates a charge circuit fault in your HVAC system.
Most commonly this …
U4
Universal
HVAC System
HVAC error code U4 means the indoor unit and the outdoor unit have lost …
U5
Universal
HVAC System
U5 on an HVAC system typically means the indoor unit fan motor has stopped …