Emergency
S 27 on Ariston Genus

Your boiler has detected that the water inside the hot water storage tank has become dangerously hot and has shut down to prevent damage or safety risks.

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.

What the manual says

Manufacturer manual

Tank overheating

From this model's manual
Verified against the Ariston Genus One 24 installation & service manual, page 45.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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