BoilerFaultCodes Frequent sooting of heat exchanger and burners - 5 Emergency
Your boiler is struggling to burn fuel properly because the internal parts are not the correct size for your gas supply, leading to a dangerous buildup of soot that must be addressed immediately.
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: Wrong injectors fitted.
Typical repair cost £200-400 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
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Chaffoteaux Flexiflame 140 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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