High
2967 on Worcester Bosch Greenstar 8000 Life

Your boiler has detected that the water temperature is changing in a way that suggests there might be a blockage or a problem with how the water is flowing inside the unit.

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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