Low
d.35 on Vaillant ecoTEC plus aquaPLUS

Your boiler is currently switching its internal components to test whether it should be sending heat to your radiators or your hot water tank.

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.

What the manual says

Manufacturer manual

Diverter valve position

From this model's manual
Verified against the Vaillant Ecotec Plus Aquaplus installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Observe the boiler for a few minutes; this is usually a normal diagnostic check rather than a fault.If the code stays on screen permanently, try resetting the boiler using the button marked with a flame or 'Reset'.Check if your heating and hot water are still working as normal.

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