BoilerFaultCodesYour boiler is unable to start up because the internal fan isn't spinning fast enough to safely clear the system before ignition.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Insufficient fan speed for ignition
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is not reaching the required speed to safely vent exhaust gases. The most common reasons are a build-up of debris within the fan assembly, a failing motor, or a blockage in the small plastic tubes that monitor air pressure. Without the fan spinning at full strength, the boiler will refuse to ignite as a safety precaution.
This fault is slightly more common in autumn and winter, as spiders or debris can block the pressure sensing tubes during periods of high wind or inactivity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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