Emergency
8.9 on Chaffoteaux Britony II 30FF

Your boiler is not burning gas correctly, which is creating soot and could be producing dangerous carbon monoxide.

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

Yellow Flames - Soot Formed

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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