BoilerFaultCodesYour boiler is continuing to run the internal pump to cool down after use, which is a normal process, but it may be taking longer than usual or indicating an internal circulation issue.
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: pump overrun
What causes this fault?
This occurs when the boiler detects that the internal temperature is remaining too high after the burners have switched off, prompting the pump to stay running to move heat away. The most common reason is a restriction in water flow or a pump that is beginning to struggle, meaning the system cannot shed heat as quickly as it should. Occasionally, it can be caused by a sensor incorrectly reporting that the heat exchanger is still hot.
This is more common in summer when radiators are turned off, as the boiler has fewer paths to dissipate heat after providing hot water.
DIY fix possible
Check that all radiator valves are fully open to allow water to circulateEnsure the system pressure is between 1.0 and 1.5 bar on the gaugeRestart the boiler to see if the status code clears after a period of cooling
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