Medium
4 07 on Ariston Clas One

Your boiler is struggling to read the temperature correctly because it has lost its connection to the room thermostat or internal sensor.

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 7 short circuit

Engineer required

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

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