High
40-50 (ll-ll) on Ariston Clas HE 35

Your boiler has detected that the internal fan responsible for safely exhausting fumes is not spinning or responding correctly, so it has shut down to keep you safe.

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

Operating control fault of the fan

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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