Medium
S 04 on Ariston Genus Premium

Your boiler is struggling to detect the temperature of your hot water, which means it cannot provide consistent or safe water for your taps and showers.

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 circuit on Domestic hot water sensor

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 05View →

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