Emergency
SOOT FORMED on Chaffoteaux Britony II 30FF

Your boiler is struggling to breathe, causing a build-up of waste material that indicates it is not burning gas cleanly, which can be dangerous.

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

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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