BoilerFaultCodesYour boiler is failing to start because the internal fan is not spinning correctly or the control board cannot confirm it is working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan voltage indication
What causes this fault?
This fault occurs when the boiler's control board sends power to the fan but does not receive the necessary electrical feedback to confirm it is spinning safely. The most common reasons are a seized fan motor due to age, a perished vacuum tube, or a failing computer board that can no longer process the fan's signal.
This fault is slightly more common in winter when the fan has to work harder to overcome heavy winds or when cold dampness affects aging electrical components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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