High
2966 B on Worcester Bosch Junior 28i

Your boiler has detected that the water inside is heating up too quickly, which usually means the water isn't flowing through the system as it should.

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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Related fault codes

E9View →224VView →

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