BoilerFaultCodesYour boiler is continuing to run the pump for a short period after the heating has switched off to safely move excess heat away from the internal components.
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 operational process rather than a breakdown, occurring when the boiler has finished heating and needs to dissipate residual heat from the heat exchanger. The pump continues to circulate water for several minutes to prevent the internal components from overheating and to protect the long-term health of the unit. You may notice this most often immediately after your thermostat has reached its target temperature and clicked off.
DIY fix possible
Check that your radiator valves are open to allow water to circulateWait up to 10 minutes to see if the code clears automaticallyEnsure there is enough water pressure shown on the boiler gauge (typically 1.0 to 1.5 bar)
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