High
Fault on Worcester Bosch Greenstar 25HE

Your boiler is struggling to burn the gas cleanly, which is causing an internal vibration or rumbling noise that requires professional attention.

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

Excessive burner noise, rumbling noises

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

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