Emergency
UNSTABLE FLAMES on Chaffoteaux Britony II 30FF

Your boiler is struggling to keep its internal fire burning steadily, which often indicates an issue with the air supply or a blockage in the exhaust system.

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) Water in gas line, ii) Faulty flue (Check terminal position and flue ducts)

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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