Medium
45 on Alpha Intec2 30SE

Your boiler has detected that the water is not circulating efficiently through your heating system, as it is coming back to the boiler much cooler than it left.

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

A too high ΔT between CH flow and return sensors has been detected

Engineer required

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

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