Emergency
FA / 306 on Worcester Bosch Greenstar i

Your boiler has detected that a flame is present even though it has commanded the gas supply to shut off, which indicates a safety-related internal fault.

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

Ionisation detected after the gas valve closed.

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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