High
Vitodens 200 on Viessmann Vitola Biferral

Your boiler has stopped working because the fan isn't spinning at the correct speed, causing the system to shut down for safety.

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

Burner control switches to lockout. Fan does not idle after auto reset (incorrect fan rpm).

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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