Medium
304 on Ariston Alteas One

Your boiler has attempted to restart itself too many times in a short period and has temporarily locked you out for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

All Boilers

DIY fix possible

Locate the Reset button on the front control panel.Press and hold the Reset button for 5 seconds.Wait for the boiler to complete its restart sequence.If the code persists, check if other gas appliances are working.

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Related fault codes

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