High
2948 on Worcester Bosch Greenstar 4000

Your boiler is struggling to keep its flame lit during start-up,, likely due to external weather conditions affecting the flue.

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 - Burner starts automatically after purging. This can be caused by strong winds.

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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