BoilerFaultCodesYour boiler has detected a problem with the fan or its internal control chip, meaning it cannot safely clear waste gases and will not start.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan error or control unit defective (speed control is not achieved)
What causes this fault?
This fault occurs when the boiler's main computer loses the ability to control or communicate with the fan that pushes exhaust fumes out of the flue. The most common reason is a mechanical failure within the fan motor or a communication error on the internal circuit board, causing the boiler to shut down for safety. In some cases, it can also be triggered by loose or damaged wiring connecting these two vital components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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