Medium
40 ❍, 50 ❍, 60 ❍, yellow ❍ on Ariston Clas One

Your boiler has lost communication with its temperature sensor, meaning it cannot accurately tell how warm your room is and may stop heating your home as a safety precaution.

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 / short circuit

Engineer required

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

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Related fault codes

607View →608View →

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