High
2967 B on Worcester Bosch Junior 28i

Your boiler has sensed a sudden, unusual temperature difference between two internal parts and has shut down to prevent overheating.

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 / heat exchanger temperature sensor differential too great

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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