Emergency
AA0033 on Ariston Micro Condens

Your boiler has detected that the water inside the heating system has reached a dangerously high temperature and has shut itself down to prevent damage or 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 Micro Condens System 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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