High
23 on Chaffoteaux Serelia 24 MFFI

Your boiler has detected that the internal exhaust fan is not spinning fast enough to safely clear fumes, so it has shut down to prevent a safety risk.

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 speed too low

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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