High
Fast flash on Worcester Bosch Greenstar 35 CDi

Your boiler is still detecting a flame even after it has been told to turn off, which means it will shut down for safety purposes.

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

Flame detected after gas shut off.

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

EAView →F7View →

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