Medium
S 25 on Ariston Genus One 30

Your boiler is struggling to read the temperature of the water in your separate hot water cylinder, which may result in no hot water or an inability to regulate its temperature.

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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Related fault codes

S 26View →

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