Low
d.11 on Vaillant ecoTEC Plus 65

Your boiler is simply reporting that a secondary pump, responsible for circulating water through your heating system, is currently not running.

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

Status of the heating circuit's shunt pump: off/on

DIY fix possible

Check if the heating system is currently calling for heatMonitor the display to see if the status changes to 'on' when demand is activeContact an engineer if the system fails to heat despite the control setting

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Related fault codes

d.10View →F.22View →

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