Medium
712 on Ariston Alteas One

Your boiler is struggling to monitor the temperature of the water returning from the second heating zone, which may prevent some of your radiators from warming 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 2)

Engineer required

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

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Related fault codes

711View →713View →

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