Low Information
D.72 on Vaillant ecoTEC

Your boiler is continuing to run its internal pump for a short period after heating your water to ensure it cools down safely and efficiently.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

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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