Low
d.20 on Vaillant ecoFIT Pure 835

Your boiler is limited to a specific maximum temperature for your hot water, which is a setting adjustment rather than a mechanical breakdown.

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

Maximum hot water set target temperature

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 30.
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

Navigate to the 'd.20' setting in the installer level menu (refer to manual)Adjust the value to your preferred maximum hot water temperaturePress the tick or 'OK' button to save the new setting

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