Error 399 - Heat sink temperature sensor error of Fan2

What does 399 mean?

The temperature sensor on the heatsink of Fan2 (likely an outdoor unit fan) is reporting an error, which could indicate overheating or a sensor malfunction.

• Faulty temperature sensor
• Fan overheating due to obstruction or malfunction
• Loose sensor connection

Click steps to track your progress.

1. 1

   Power off the outdoor unit and allow it to cool down completely.

2. 2

   Check the heatsink temperature sensor connections for Fan2 for any looseness.

3. 3

   Ensure proper airflow around Fan2; if the issue continues, contact support as the sensor or fan may be faulty.