Medium
722 on Ariston Alteas One

Your boiler has detected that the secondary heating circuit is getting too hot, likely due to a circulation or sensor issue.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

Overheating in zone 2

DIY fix possible

Check that all radiator valves in the secondary zone (e.g. upstairs or underfloor heating) are fully open.Ensure there is no trapped air in the system by bleeding the radiators.Restart the boiler to see if the fault clears.

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