Error Code	Symptom	Fault Type	Guide
E1	Indoor unit displays E1 and cooling stops intermittently	Indoor/Outdoor Communication Fault	View Details
E2	Indoor unit shows E2 and evaporator coil ices up or unit stops cooling	Evaporator Coil Temperature Sensor (T1) Fault	View Details
E3	Indoor unit displays E3 and outdoor unit does not run or stops shortly after starting	Outdoor Unit Protection / High-Pressure or Overload Trip	View Details
E4	Indoor unit shows E4 and cooling performance is poor or unit stops after short run	Evaporator Coil Freeze Protection / Low-Temperature Lockout	View Details
E5	Indoor unit displays E5 and outdoor unit does not start or shuts down quickly	Overcurrent / Compressor Overload Protection	View Details
E6	Indoor unit shows E6 and system does not respond to cooling commands	Indoor Fan Motor Fault / Feedback Error	View Details
E7	Indoor unit displays E7 and outdoor unit does not operate	Mode Conflict / Indoor-Outdoor Mismatch or Reversing Valve Error	View Details
E8	Indoor unit shows E8 and unit stops with strong airflow or unusual noise	Indoor Fan Overload / Over-speed Protection	View Details
E9	Indoor unit displays E9 and may leak water or shut down unexpectedly	Full Drain Pan / Water Level Sensor Fault	View Details
F0	Indoor unit shows F0 and system does not cool properly	Refrigerant Undercharge / Low Refrigerant Protection	View Details
F1	Indoor unit displays F1 and runs erratically or not at all	Indoor Ambient Temperature Sensor (Room Thermistor) Fault	View Details
F2	Indoor unit shows F2 and unit may short cycle or not reach set temperature	Evaporator Pipe Temperature Sensor (T3) Fault	View Details
F3	Indoor unit displays F3 and outdoor unit may not operate correctly in heating mode	Outdoor Ambient Temperature Sensor Fault	View Details
F4	Indoor unit shows F4 and heating or cooling capacity is unstable	Outdoor Coil Temperature Sensor Fault	View Details
F5	Indoor unit displays F5 and system may shut down in heating mode	Defrost Sensor / Outdoor Coil Low-Temperature Fault	View Details
F6	Indoor unit shows F6 and outdoor fan may not operate correctly	Outdoor Fan Motor Fault	View Details
F7	Indoor unit displays F7 and system may not start or may shut down unexpectedly	Outdoor EEPROM / PCB Memory Fault	View Details
F8	Indoor unit shows F8 and unit may not respond to remote or may operate erratically	Indoor EEPROM / PCB Memory Fault	View Details
F9	Indoor unit displays F9 and louver may not move correctly	Indoor Louver Stepper Motor Fault	View Details
P0	Indoor unit shows P0 and system will not start or stops shortly after starting	Inverter Module / IPM Protection	View Details
P1	Indoor unit displays P1 and system may not run or may shut down under load	High/Low Voltage Protection	View Details
P2	Indoor unit shows P2 and outdoor unit stops, especially in high ambient temperatures	Compressor Overheating / High Discharge Temperature Protection	View Details
P3	Indoor unit displays P3 and system may not start in heating or may shut down	Low Outdoor Ambient Protection / Compressor Low-Temperature Protection	View Details
P4	Indoor unit shows P4 and system may not run or may shut down under heavy load	Inverter Module Overheating / IPM Temperature Protection	View Details
P5	Indoor unit displays P5 and system may not operate in heating mode	Defrost Protection / Outdoor Coil Over-icing	View Details
–	Carrier air conditioner blows warm air in cooling mode	Loss of Cooling / Reversing Valve or Refrigerant Issue	View Details
–	Carrier air conditioner cycles between heating and cooling unexpectedly (heat pump models)	Reversing Valve or Control Logic Fault	View Details
–	Carrier air conditioner emits a burning or electrical smell	Overheating Electrical Component	View Details
–	Carrier air conditioner emits a musty or moldy smell when starting	Biological Growth on Evaporator Coil and Drain Pan	View Details
–	Carrier air conditioner frequently trips the circuit breaker	Overcurrent / Electrical Overload	View Details
–	Carrier air conditioner indoor unit display is blank but unit still runs with remote	Display Board Failure	View Details
–	Carrier air conditioner indoor unit freezes up with ice on the coil	Evaporator Coil Icing	View Details
–	Carrier air conditioner indoor unit louvers do not move or are stuck in one position	Louver Mechanism Jam	View Details
–	Carrier air conditioner indoor unit runs but outdoor unit does not start	Outdoor Unit Non-Start	View Details
–	Carrier air conditioner makes loud rattling or buzzing noises during operation	Mechanical Vibration / Loose Components	View Details
–	Carrier air conditioner remote control does not operate the indoor unit	Remote Control / IR Receiver Failure	View Details
–	Carrier air conditioner runs but does not cool the room effectively	Insufficient Cooling Capacity / Performance Degradation	View Details
–	Carrier air conditioner turns ON but shuts OFF after a few minutes	Short Cycling	View Details
–	Carrier air conditioner will not turn ON at all (no lights, no response)	No Power / Control Circuit Dead	View Details
–	Carrier outdoor unit is very loud or vibrates excessively	Outdoor Unit Vibration / Mounting Issue	View Details
–	Carrier outdoor unit runs but indoor fan does not blow air	Indoor Blower Failure	View Details
–	Water leaking from the indoor Carrier air conditioner onto the wall or floor	Condensate Drainage Failure	View Details

Carrier Air Conditioners Error Codes

No matching codes found