BoilerFaultCodesYour boiler is preparing to start the heating process by running the internal fan to clear out the combustion chamber.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: fan pre-run
What causes this fault?
This is not actually a fault, but rather a normal part of the boiler's starting routine where the fan spins up to clear any residual gases from the burner area. It occurs every time the system receives a request for heat or hot water to ensures the appliance is safe to ignite. If the boiler stays stuck on this code without firing up, it usually indicates the fan cannot reach the required speed or the air pressure switch isn't detecting enough airflow.
DIY fix possible
This is a normal status code, not a fault; you do not need to do anything.Wait a few moments for the boiler to complete its start-up sequence.If the code stays on screen for a long time without the boiler firing, try a simple reset.
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