BoilerFaultCodesYour boiler's fan is spinning faster than it should, which is preventing the system from safely managing the air and gas flow needed for heating.
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 too high.
What causes this fault?
This fault occurs when the boiler's internal computer loses the ability to control how fast the fan is spinning, causing it to run at an unsafe maximum speed. The most common reason is a communication failure between the fan motor and the main control board, often caused by a worn-out component or a loose electrical connection. Because the boiler cannot accurately balance the air and gas mixture, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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