BoilerFaultCodesYour boiler is briefly running the internal pump after providing hot water to help cool down 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: DHWmode:Pumpoverrun
What causes this fault?
This occurs when the boiler finishes heating your tap water and needs to dissipate the high heat remaining inside the heat exchanger. The internal pump continues to run for a short period to move this residual heat away from the sensitive internal components and out into the pipework. This is a normal safety function designed to protect the boiler's lifespan rather than a sign of a mechanical failure.
This status may appear more frequently during the summer months when the boiler is only used for hot water and the central heating system is cold.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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