BoilerFaultCodesYour boiler is currently running a self-cleaning cycle to remove air bubbles from the pipes and pump.
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: Venting function (automatically activates one-off venting sequence where pump switches on and off)
What causes this fault?
This occurs when the boiler detects air pockets within the internal pipework or the pump, often following a recent repair or after the system has been drained and refilled. To prevent damage and ensure quiet operation, the boiler automatically triggers a cleaning sequence to push this trapped air out through the automatic air vent. It is a normal protective measure rather than a mechanical failure.
This is most common in autumn when homeowners first turn their heating back on after the summer or after annual maintenance work has been performed.
DIY fix possible
Wait for approximately 10 to 15 minutes for the sequence to complete automaticallyEnsure your radiator valves are open to help move air through the systemCheck the system pressure gauge and top up to 1.5 bar if it has dropped
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