Medium
S 04 on Ariston Genus One 30

Your boiler is struggling to detect the temperature of your hot water supply, so it has stopped providing hot water to prevent it from overheating.

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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