Medium
723 on Ariston Alteas One

Your boiler has detected that the third heating zone is getting too hot, likely due to a circulation problem or a faulty sensor in that specific area of your home.

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 3

DIY fix possible

Check that all radiator valves in Zone 3 are open and not turned off.Ensure there are no obstructions around any localized zone pumps or valves.Try resetting the boiler to see if the error was a temporary sensor glitch.

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Related fault codes

722View →101View →

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