Carrier air conditioner error codes

Displayed on the indoor unit or remote when a fault is detected. Always isolate power before inspecting a unit — repairs belong to a qualified technician.

CodeMeaningApplies to
E1 High pressure protection in the refrigeration circuit. All models Details
E2 Evaporator coil temperature sensor fault. All models Details
E3 Low pressure protection. All models Details
E4 Compressor discharge temperature protection. All models Details
E5 Overcurrent or overload protection. All models Details
E6 Communication error between indoor and outdoor units. All models Details
EC Refrigerant leak detection alarm. All models Details
F0 Low refrigerant protection. All models Details
P0 High voltage protection. All models Details
P1 Low voltage protection. All models Details
P4 Fan speed fault. All models Details