Fault 33 — Power supply voltage below minimal level or internal fuse failure

What does 33 mean?

The boiler's power supply voltage is below the minimum operating level, or an internal fuse has failed. This prevents the boiler from receiving adequate power to function.

• Power supply voltage is below minimal operating level
• internal fuse failure.

Click steps to track your progress.

1. 1

   Check the main power supply to the boiler and ensure the circuit breaker has not tripped.

2. 2

   If accessible, visually inspect for any signs of an internal fuse failure within the boiler's control unit.

3. 3

   Press the reset button R on the boiler.

4. 4

   If the fault persists, a qualified technician should check the power supply or replace the control unit if a fuse is confirmed failed.