BoilerFaultCodesYour boiler's fan is failing to maintain a steady speed, which prevents the system from safely drawing in air and exhausting gases.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan speed varies
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is spinning at an inconsistent or incorrect speed to safely clear exhaust gases. The most common reason is a mechanical failure within the fan motor or a communication error caused by damaged wiring or a faulty control board. Without a steady and predictable airflow, the boiler shuts down as a safety precaution to prevent improper combustion.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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