High
A8 on Worcester Bosch Highflow 440 CDi

Your boiler has detected that the internal pump, which pushes heat around your home, is not spinning correctly and the system has shut down to prevent damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Interrupted water circulation pump with anti-seizure

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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