Medium
EE9999 on Ariston Clas One

Your boiler has blocked itself for safety because it was reset too many times in a short period.

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

More than 5 RESETS of the boiler in 15 minutes.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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