Your boiler is currently running an automatic program to remove trapped air from the system, which usually happens during startup 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: The heating circuit and hot water circuit are purged
What causes this fault?
This occurs when air has entered the heating system, often after the boiler has been drained, a radiator has been changed, or the system pressure has dropped. To prevent damage and ensure quiet operation, the boiler automatically runs a program to push this trapped air out of the internal pipework and heat exchanger.
This is most common in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
DIY fix possible
Wait approximately 6 to 7 minutes for the program to finish automaticallyEnsure your radiator valves are fully open to allow air to moveOnce the program ends, check if the water pressure is still within the green zone (1.0 to 1.5 bar)
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