ON HEATING MODE, IF THE INDOOR UNIT COIL TEMPERATURE SENSOR DETECTS A ROOM TEMPERATURE LOWER THAN 5? OR MORE AFTER THE COMPRESSOR WORKS FOR 8 MINUTES, THE AC UNIT WILL DISPLAY THE F8 CODE.
REPAIR:
1) CHECK IF THE 4-WAY VALVE IS WELL CONNECTED OR NOT
2) IF THERE IS NO PROBLEM WITH THE CONNECTION AND THE CONTROL BOARD, PLEASE CHECK THE VALVE ITSELF