Medium
713 on Ariston Alteas One

Your boiler has lost the ability to monitor the temperature of water returning from your third heating zone, which may prevent that specific area from heating up correctly.

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

Return sensor defective (zone 3)

Engineer required

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

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Related fault codes

703View →711View →712View →

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