BoilerFaultCodesYour boiler has shut down because the exhaust gases are getting too hot, indicating a potential blockage or safety issue in the flue pipe.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Flue temperature signals overheating, the flue gas discharge path needs checking, Try resetting the boiler
What causes this fault?
This fault occurs when the internal sensors detect that the exhaust gases are reaching dangerous temperatures that could damage the boiler or its surroundings. The most common reason is a buildup of debris or scale within the heat exchanger or a physical blockage in the flue pipe that prevents heat from escaping properly. In some cases, it can also be triggered by a faulty sensor sending an incorrect temperature reading to the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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