Emergency
Flue spillage device on Worcester Bosch 24CDi BF

Your boiler has detected that gases are not safely escaping through the flue and has shut itself down to protect your home from harmful fumes.

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.

What the manual says

Manufacturer manual

The D.H.W. demand indicator will flash (approximately 5 times per second).

From this model's manual
Verified against the Worcester Bosch 24cdi Bf installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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