BoilerFaultCodesYour boiler is simply running a self-cleaning routine to remove trapped air from the system and is not actually at fault.
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: Purging: The internal pump is cyclically actuated. The heating circuit and the domestic hot water circuit are adaptively purged by automatically switching the circuits using the automatic air vent.
What causes this fault?
This code appears when the boiler detects potential air pockets inside the internal pipework or heat exchanger. It physically triggers the pump to pulse on and off to push those air bubbles toward the automatic bleed valve so they can be safely released. This usually happens after the system has been drained for a repair or when the boiler is first powered on.
This is more common in autumn when homeowners turn their heating back on for the first time or after radiators have been bled and the system re-pressurised.
DIY fix possible
Wait for 5 to 10 minutes for the program to finish automaticallyEnsure your radiator valves are open to help air move through the systemCheck the boiler pressure gauge is in the green zone (typically 1 to 1.5 bar)
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