Medium
d3 on Worcester Bosch Ri 25 HE

Your boiler has automatically shut down because an external safety device, typically linked to your underfloor heating, has detected that the water temperature is too high.

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

External temperature limiter has triggered (e.g. floor heating).

Engineer required

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

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