BoilerFaultCodesYour boiler has detected that the fan was running or air was moving when it shouldn't have been, causing the system to lock out for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Airflow present during last 24 hour
What causes this fault?
This fault occurs when the boiler's control board detects air movement or fan activity at a time when the system should be idle. It is usually caused by a faulty fan that is spinning at the wrong speed, a sticking internal component, or a communication error with the main circuit board. Because the boiler cannot accurately verify that it is safe to ignite, it shuts down as a protective measure.
This fault can be more frequent during periods of very high winds, as strong gusts blowing directly into the flue terminal can occasionally spin the fan or trigger the air sensors incorrectly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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