High
2966 B on Worcester Bosch 24 RSF

Your boiler is overheating because the water inside it is getting too hot too quickly, often caused by a blockage or a pump that isn't moving the water fast enough.

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

Flow temperature rise in heat exchanger too rapid

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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