BoilerFaultCodesTechnical description
Fan not running at maximum speed.
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is not reaching the necessary speed to safely expel exhaust gases. The most common reasons are a build-up of dirt within the fan or a blockage in the small tubes that monitor air pressure. If the fan cannot create enough airflow, the boiler will prevent ignition to ensure carbon monoxide doesn't build up inside the unit.
This fault can be more frequent during autumn or windy weather, as debris or strong gusts can obstruct the flue or put extra strain on a struggling fan motor.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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