Carrier · Air Conditioner error code
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Guide · Air ConditionerNormal defrost lasts a few minutes, with the outdoor fan off, steam rising and aux heat on. A unit that stays in defrost points to a defrost thermostat/sensor that never opens, a board fault, or a reversing valve that doesn't shift back. Separate normal behaviour from a real fault first.
Guide · Air ConditionerAll of these are normal parts of a defrost cycle: the unit reverses briefly to melt frost, the fan stops, melt water steams off the coil and backup heat may come on. The wrong turn is treating a normal defrost as a failure, or the opposite, dismissing a unit that is truly stuck in defrost or encased in ice. The job is to separate the two.
Guide · Air ConditionerWeak cooling has cheap mechanical causes that look like a charge problem to a customer: a plugged condenser coil, a failed run capacitor or a slow outdoor fan. The wrong turn is adding refrigerant before checking airflow and the capacitor; that hides the real fault, and a system that is truly low has a leak that must be found by a certified technician.
Carrier · Air Conditioner
E0 / EH 00
Indoor EEPROM / memory fault
Carrier · Air Conditioner
E1 / EL01
Indoor-outdoor communication error
Carrier · Air Conditioner
E3 / EH 03
Indoor fan speed out of range
Carrier · Air Conditioner
E4 / EH 60
Indoor room temperature sensor (T1) fault
Carrier · Air Conditioner
EC / EL0C
Refrigerant leak detection
Carrier · Air Conditioner
EH 02
Zero-crossing signal not detected