Medium
1 1 6 on Ariston HS Premium

Your boiler has detected that the temperature sensor for your underfloor heating system is disconnected or faulty, meaning it cannot safely regulate the warmth of the floor.

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

Open floor thermostat

Engineer required

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

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