Medium
4 11 on Ariston E-Combi One 30

Your boiler is struggling to communicate with your thermostat because of a loose connection or damaged wiring in the sensor circuit.

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 1

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 12View →4 13View →

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