Low Information
S.27 on Vaillant ecoTEC plus Regular

Your boiler is temporarily running the pump to circulate water and cool down the engine after it has finished heating.

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

What causes this fault?

This occurs when the boiler completes a heating cycle and needs to dissipate residual heat from the internal heat exchanger. The pump continues to run for a few minutes to move hot water away from the unit and prevent the internal components from overheating. It is a normal safety function rather than a mechanical failure.

DIY fix possible

Check that the radiator valves are open to allow water to circulateMonitor the display to see if the status code changes to a normal heating modeEnsure there is enough water pressure in the system by checking the gauge

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