BoilerFaultCodesYour boiler is currently running a self-cleaning sequence to remove air bubbles from the internal heating circuit, which usually happens when it is first turned on or after maintenance.
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: Ventilation program
What causes this fault?
This code appears when the boiler detects that air might be trapped within the internal heat exchanger or pipework. It physically triggers a sequence where the pump runs at varying speeds to force these air bubbles toward the automatic air vent so they can be safely expelled. This process typically occurs automatically after the boiler has been drained for a repair or when the power is first turned on.
This is more common in autumn when homeowners turn their heating systems back on for the first time or after summer radiator maintenance.
DIY fix possible
Wait approximately 10 to 15 minutes for the automated program to finishEnsure your radiator valves are open to help move air through the systemOnce the countdown or message disappears, the boiler should return to normal operation automatically
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