Emergency
AA 7755 on Ariston Clas One

Your boiler has detected an issue with the system that removes waste gases, meaning it has shut down to ensure your home remains safe.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Problem with the flue stat

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

607View →608View →A01View →

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