High
40-60-70 (ll-ll-ll) on Ariston Clas HE 35

Your boiler is failing to register that the internal fan has stopped, likely due to a stuck sensor or internal blockage.

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 off but air pressure switch fails to return to off position

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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