Medium
50 on Atag S 25CR

Your boiler is struggling to detect the temperature of your hot water supply, so it has safely switched off your hot water to prevent an error.

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

T3 (DHW) sensor error (e.g. open, short circuit, out of range)

Engineer required

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

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