Medium
7 11 on Ariston E-Combi One 30

Your boiler is having trouble 'sensing' the temperature of the water returning from your radiators, which prevents it from heating your home 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

Zone 1 return sensor defective

Engineer required

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

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