Low
D.020 on Vaillant ecoTEC plus

Your boiler is currently displaying its setting for the maximum hot water temperature rather than indicating a fault.

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

Settingthemax.domestichotwatertemperature

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 73.
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

Wait for the display to return to the standard operating screen automaticallyPress the 'i' button on the front panel to exit the menuIf the screen stays stuck, simply turn the boiler off at the fused spur for 30 seconds and switch it back on

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Related fault codes

D.021View →D.022View →

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