High
S 27 on Ariston Genus 30 Plus

Your boiler has detected that the water inside its internal storage tank is reaching dangerously high temperatures and has shut itself down to prevent damage or safety risks.

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

Tank overheating

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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