Medium
S 25 on Ariston Genus 27

Your boiler has lost connection with the sensor that monitors the temperature of your hot water tank, meaning it cannot heat your water correctly.

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

Tank sensor open

Engineer required

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

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S 26View →

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