High
A33 on Ariston Genus 24 MFFI

Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not spinning or communicating correctly, causing the system to stop working as a safety precaution.

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

Problem with 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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