High
6 12 on Ariston Clas HE Evo

Your boiler has detected that the internal fan responsible for clearing exhaust gases is not spinning or reporting its speed correctly, so it has 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

Incorrect measurement of fan speed

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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