Description: Outdoor Unit PCB Abnormality.
Method of Malfunction Detection:
- The system checks if the microprocessor is working in order.
- The system checks if the zero-cross signal comes in properly.
Malfunction Decision Conditions:
- The microprocessor program runs out of control.
- The zero-cross signal is not detected.
Supposed Causes:
- Defective outdoor unit PCB
- Broken harness between PCBs
- Noise
- Momentary fall of voltage
- Momentary power failure, etc.
Troubleshooting Procedure
