Low
d.18 on Vaillant ecoTEC plus System

This is just an information code showing how your boiler's internal water pump is currently set to behave, which is normal operation rather than a system error.

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 operating mode: 1=Comfort (continuously operating pump), 3=Eco (intermittent pump mode)

DIY fix possible

This code appears during normal navigation of your boiler settings menu.If you wish to change the behavior, refer to your user manual's section on pump modes.If no other error codes are showing, no action is required.

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d.17View →d.19View →

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