High Lockout
F.32 on Vaillant ecoTEC Pro / ecoTEC Plus

Your boiler has stopped working because the internal fan that safely removes exhaust gases is either stuck or not communicating correctly with the system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Fan error

What causes this fault?

This fault occurs when the boiler's control system detects that the internal fan is not spinning at the correct speed or has failed to start entirely. The most common reason is that the fan motor has burnt out or become seized, though it can also be caused by a communication failure between the fan and the main circuit board.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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