Emergency
YELLOW FLAMES / SOOT FORMED on Chaffoteaux Britony Duo 55

Your boiler is not burning fuel cleanly, which can create dangerous gases, so you should stop using it immediately.

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

I) Heating body fins blocked; II) Primary air supply restricted; III) Wrong injectors

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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