High
2967 on Worcester Bosch Greenstar 4000

Your boiler has detected that water isn't flowing through its internal heating system as freely as it should, so it has shut down to prevent parts from 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

The temperature difference between supply temperature sensor and temperature sensor at heat exchanger is too large

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

2965View →2966View →

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