Emergency
Slow flashes on Worcester Bosch Greenstar 25CDi

Your boiler is still sensing a flame even though it has tried to shut off the gas, which is a safety concern that requires a professional inspection.

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 after gas shut off. Check gas valve and wiring to gas valve. Clean condensation trap and check electrode assembly. 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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