HEX: 89 - Combustion air fan interruption

Fault Details:

• The combustion air fan is interrupted or shorted to supply voltage (UB).

Recommended Solution:

1. Perform an electrical check of the fan motor.

2. Remove the top cover of the heater and inspect the fan for rub marks, scratches, or other damage.

3. Ensure the fan moves freely.

Note: Fault code meanings can vary depending on the model and controller. If you’re unsure, contact Heatso directly.