Emergency
306 / FA on Worcester Bosch Greenstar CDi Compact

Your boiler is continuing to detect a flame even after it should have turned off, indicating a safety sensor or valve 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 burner stop

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

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