High
2953 on Worcester Bosch Greenstar 8000 Style

Your boiler is failing to light the internal burner properly during low-power operation, meaning it cannot provide you with heating or hot water safely.

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

No flame signal with low output.

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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