Emergency
F7 on Worcester Bosch Greenstar R29 40 HE

Your boiler has detected that the internal flame is still burning even though it should have turned off, which is a significant safety precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Flame detected even though appliance switched off. Check electrode assembly, dry pcb. Flue clear?

Engineer required

This is a emergency 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 →F0View →

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