Air Conditioning Error E1, E4, E5 & H6 (Gree, Daikin, Mitsubishi): Causes & Fix
During a summer heatwave or winter cold snap, your air conditioner suddenly stops blowing air and flashes error codes E1, E4, E5 or H6. Unlike Error E6 (communication fault), these codes indicate critical compressor pressure, temperature or fan motor lockouts. Here is what each code means.
Error E1: Compressor High-Pressure Protection
On Gree, Daikin, HTW, Johnson and Baxi units, Error E1 means refrigerant pressure has exceeded 42 bar. In summer cooling mode, this happens when the outdoor condenser coil is choked with dust or the outdoor fan stops spinning. In winter heating mode, it is caused by clogged indoor filters trapping heat inside the indoor unit.
Error E4: Compressor High Discharge Temperature (>115 °C)
Error E4 triggers when the compressor dome overheats above 115 °C—almost always caused by a refrigerant gas leak (R32 or R410A) starving the compressor of cooling return gas.
Error E5 (Overcurrent) & Error H6 (Indoor Fan Motor Stall)
Error E5 indicates an electrical current spike on the inverter PCB, while Error H6 means the indoor blower fan is jammed or its Hall sensor is not sending RPM feedback.
Switch off the AC circuit breaker at your consumer unit for 10 minutes to reset the PCB. If the error returns, call our 24/7 HVAC repair technicians in Barcelona, Girona, Badalona and Sabadell on 936 94 00 23.
FAQ
Is it dangerous to keep resetting an air conditioner showing Error E4?
Yes. Repeatedly forcing the compressor to run with low refrigerant and Error E4 will burn out the compressor windings, turning a simple leak repair and regas into a full unit replacement.