Medium
4 13 on Ariston E-Combi One

Your boiler is struggling to read the temperature from an external wall controller or zone sensor, which prevents it from knowing when to turn the heating on.

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 ZONA 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

4 11View →4 12View →

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