Fault code 64 — Communication between Indoor & Outdoor unit Fault

What does 64 mean?

Communication has been lost between the indoor and outdoor units. This could be due to wiring issues, faulty communication cables, or problems with the control boards.

• The indoor unit and the outdoor unit are not connected properly
• The communication cable is connected loosely
• The communication cable between the indoor unit and the outdoor unit fails or the cable between the indoor control board to terminal fails or the cable between the outdoor control board to the terminal fails
• The indoor control board fails
• The outdoor control board fails

Click steps to track your progress.

1. 1

   Ensure the indoor and outdoor units are correctly connected according to the wiring diagram.

2. 2

   Check that the communication cable is securely connected at both ends.

3. 3

   Replace the communication cable if it appears damaged.

4. 4

   If the wiring is correct, the indoor or outdoor control board may need to be replaced.