High
273 on Worcester Bosch Greenstar 4000

Your boiler has detected that it cannot safely ignite or maintain its flame, so it has automatically shut down to prevent any risk.

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

Operation of burner and fan interrupted

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

224View →227View →

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