Low
d.45 on Vaillant ecoFIT Pure 425

This is not an error code, but a technical setting that allows you to adjust the temperature at which your heating system starts operating.

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

Value for the base point of the heating curve

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 31.
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

Press the menu button to enter the diagnostic settingsNavigate to setting d.45 using the plus or minus buttonsAdjust the numerical value to your preferred base temperature and press OK to save

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Related fault codes

d.43View →d.47View →

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