Medium
701 on Ariston Alteas One

Your boiler has detected a fault with the heating zone 1 flow temperature sensor, which means it cannot accurately monitor the water temperature leaving the boiler.

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

E-Combi EvoE-System EVOClas HE evo combiClas he evo system

Engineer required

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

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Related fault codes

702View →703View →705View →

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