Problems with your Carrier air conditioning system would often come up with error codes that would be displayed on the screen of your remote control, or indoor unit. Any problems with your indoor or outdoor unit would show an error code as the air conditioner detects an issue with your aircon.
In this complete guide, we’ll show you the different indoor and outdoor Carrier fault codes that you may encounter. These error codes will indicate the problem with your air conditioning system so you can troubleshoot the underlying issue with your AC system.
Indoor Error Codes
Code |
Possible Cause |
E0 |
Indoor unit EEPROM parameter error |
E1 |
Indoor / outdoor units communication error |
E3 |
Indoor fan speed has been out of control |
E4 |
Indoor room temperature sensor T1 open circuit or short circuit |
E5 |
Evaporator coil temperature sensor T2 open circuit or short circuit |
EC |
Refrigerant Leakage Detection |
F1 |
Outdoor ambient temperature sensor T4 open circuit or short circuit |
F2 |
Condenser coil temperature sensor T3 open circuit or short circuit |
F3 |
Compressor discharge temperature sensor T5 open circuit or short circuit |
F4 |
Outdoor unit EEPROM parameter error |
F5 |
Outdoor fan speed has been out of control |
P0 |
IPM malfunction or IGBT over-strong current protection |
P1 |
Over voltage or over low voltage protection |
P2 |
High temperature protection of compressor top diagnosis and solution |
P4 |
Inverter compressor drive error |
P5 |
Mode conflict |
P6 |
Compressor voltage protection |
Outdoor Error Codes
Code |
Possible Cause |
E0 |
Outdoor EEPROM malfunction |
E2 |
Indoor/outdoor units communication error |
E3 |
Communication malfunction between IPM board and outdoor main board |
E4 |
Open or short circuit of outdoor unit temperature sensor |
E5 |
Voltage protection |
E8 |
Outdoor fan speed malfunction |
F1 |
No A Indoor unit coil outlet temperature sensor or connector of sensor is defective |
F2 |
No B Indoor unit coil outlet temperature sensor or connector of sensor is defective |
F3 |
No C Indoor unit coil outlet temperature sensor or connector of sensor is defective |
F4 |
No D Indoor unit coil outlet temperature sensor or connector of sensor is defective |
F5 |
No E Indoor unit coil outlet temperature sensor or connector of sensor is defective |
P1 |
High pressure protection |
P2 |
Low pressure protection |
P3 |
Current protection of compressor |
P4 |
Temperature protection of compressor |
P5 |
High temperature protection of condenser |
P6 |
IPM module protection |
Other Carrier Error Codes
Code |
Possible Cause |
DN |
Communication error between main board and EXV. |
EC |
Refrigerant leakage detection. |
EE |
Memory card error. |
EN |
Frequency limitation for module circuit protection. |
EU |
Frequency limitation for module temperature protection. |
FH |
Frequency limitation for freeze protection. |
H1 |
Defrost or heating oil return cycle. |
H3 |
Compressor overheat protection. |
H5 |
IPM Protection. |
H7 |
Compressor speed reduction. |
HC |
PFC protection malfunction. |
HE |
Compressor demagnetizing protection. |
L9 |
Compressor high voltage protection. |
LC |
Compressor start-up failure. |
LD |
Compressor phase loss protection. |
LE |
Compressor stalling. |
LF |
Compressor over-speed protection. |
LP |
Indoor and outdoor units mismatch. |
PA |
Input current protection. |
PC |
Current sensor malfunction. |
PD |
Current sensor miss-wiring protection. |
PF |
Inverter board ambient temperature sensor malfunction. |
PH |
High voltage protection. |
PL |
Low voltage protection. |
PP |
Abnormal input AC voltage. |
PU |
Capacitor charging malfunction. |
Related article: Carrier Aircon Troubleshooting Guide
Luce is your trusted and affordable Singapore aircon servicing. We have a team of professional technicians who have decades of experience in the aircon industry. You can count on us and on them to find the issue and fix it!