BoilerFaultCodesYour boiler is continuing to run its internal pump for a short period after heating your water to ensure it cools down safely and efficiently.
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 time after warm start
What causes this fault?
This is a normal operational feature rather than a mechanical failure. It occurs when the boiler keeps the internal pump running for a few minutes after heating your water to move residual heat away from the heat exchanger and protect the internal components. This prevents the boiler from overheating and ensures it stays in good condition for its next use.
DIY fix possible
Check that at least one radiator valve (the bypass radiator) is fully openMonitor the boiler to see if the code clears automatically after a few minutesEnsure the system water pressure is between 1.0 and 1.5 bar on the digital display
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A boiler cover plan would cover faults like D.72 — no call-out fees, no surprises.
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