Medium
4 12 on Ariston Clas Net One

Your boiler is having trouble communicating with the temperature sensor for your secondary heating zone, meaning that specific area may not heat 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

Room sensor circuit open or short circuit 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

4 11View →4 13View →

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