BoilerFaultCodesYour boiler has stopped working because its internal fan, which safely exhausts gases, is not communicating correctly with the main control board.
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 – tachometer signal interrupted for 1 hour or longer
What causes this fault?
This fault occurs when the boiler's control board loses track of how fast the fan is spinning, meaning it can no longer safely manage the flow of air and exhaust gases. The most common reason is a mechanical failure within the fan motor or a loose electrical connection that prevents the speed signal from reaching the main computer. In some cases, a fault on the control board itself means it can no longer 'hear' the fan, even if the fan is spinning correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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