BoilerFaultCodesYour boiler is performing a routine self-cleaning cycle to prevent internal parts from getting stuck during periods of inactivity.
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: Anti-seizing functn. active
What causes this fault?
This occurs when the boiler has been sitting idle for a long period without a request for heating or hot water. To prevent the internal pump and diverter valve from seizing up due to inactivity, the system automatically triggers a brief movement cycle to keep all mechanical components lubricated and moving freely.
This display is most common during the summer months when the central heating is turned off and the boiler is used less frequently.
DIY fix possible
Wait for 30 to 60 seconds for the operation to completeEnsure the boiler power remains switched onMonitor the display to confirm the code clears automatically
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