Medium
4 07 on Ariston Clas HE 24

Your boiler is struggling to read the temperature because the connection to your thermostat or the internal room sensor is faulty or disconnected.

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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