Emergency
AA0033 on Ariston Genus 24 MFFI

Your boiler has switched itself off because the water inside it has become dangerously hot and is overheating.

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

The heating flow temperature exceeds 100°C during operation

From this model's manual
Verified against the Ariston Genus 24 Mffi Combi installation & service manual.
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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