BoilerFaultCodesYour boiler is temporarily running the internal pump to cool the system down after it has finished heating your home or water.
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 is a normal function of the boiler rather than a mechanical failure. It occurs when the burner stops firing and the internal pump continues to circulate water to dissipate residual heat from the heat exchanger. This prevents the internal components from overheating and helps extend the lifespan of the appliance.
DIY fix possible
Wait for the code to disappear naturally as it is a normal part of the boiler's operationEnsure at least one radiator with a manual valve is left fully open to maintain water flowCheck that your system pressure is between 1.0 and 1.5 bar on the display
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
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