Upon receiving the operating command signal (serial signal) from the internal control, the external unit performs its function.
• Inverter current detection and current release operation.
• Overload detection and prevention operation by the transistor module (Compressor stop function).
• The compressor and the external fan stop when the serial signal is off (when the serial signal does not reach the external control board due to signal system problems).
• Transfer of information about the operation (serial signal) from the outdoor unit to the indoor unit.
• Detection of external temperature and control of operation speed.
• Defrost control during heating operation (temperature measurement by external heat exchanger and control of the 4-way valve and external fan).
