PC40 — Communication error between outdoor main chip and compressor driven chip

What does PC40 mean?

There is a communication failure between the main control chip and the compressor driver chip in the outdoor unit.

• Faulty connection between the chips
• Defective main control chip
• Defective compressor driver chip

Click steps to track your progress.

1. 1

   Check the electrical connections between the main control board and the compressor driver.

2. 2

   Reset the unit by turning off the power breaker for 30 seconds, then restoring it.

3. 3

   If the error persists, professional diagnosis is needed to determine which chip or connection is faulty.