Emergency
6d on Worcester Bosch Highflow 440 CDi

Your boiler has detected that a flame is still present inside the unit even though it should have turned off, which suggests a safety control issue.

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 valve switched off

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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