High
FC on Viessmann Vitodens

Your boiler has detected an issue with the internal ventilation system that pushes gases out, so it has safely shut down to prevent unsafe operation.

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

Electronic fan control (control unit) at fault

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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