High
2966 on Worcester Bosch 1000

Your boiler is shutting down because it is heating up much faster than the water can move through the system, often caused by a circulation blockage or a failing internal pump.

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

What causes this fault?

Rapid heating fault

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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Related fault codes

224View →227View →2966View →

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