BoilerFaultCodesYour boiler is continuing to circulate water after the heating or hot water has been turned off to safely dissipate excess heat.
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 needs to move residual heat away from the internal heat exchanger after the burner has switched off. It is a standard safety function designed to protect the internal components from overheating and to prevent the water from boiling inside the pipes. If this remains on the screen for an unusually long time, it may indicate that water is not flowing freely through your system bypass.
DIY fix possible
Check that at least one radiator (typically the one in the hallway with no thermostat) is turned fully on.Ensure your magnetic system filter, if fitted, is not blocked.Wait up to 10 minutes to see if the code clears automatically as the system cools down.
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