: DC Link Low Voltage . The DC voltage has dropped below 140V.

: Discharge Temperature Error . The discharge temperature has exceeded 130°C, likely due to a faulty discharge thermistor or low refrigerant.

: Communication Error . This is one of the most common codes, signifying a communication failure between the indoor and outdoor units. It often requires a technician to check for loose wiring or a faulty PCB.

: Indoor Temperature Sensor Error . This usually indicates an open or closed circuit in the indoor air thermistor.

: Inverter/Compressor Error . Points to a problem with the compressor power supply or phase.