Low
d.45 on Vaillant ecoFIT Pure 435

This is a settings menu adjustment rather than a fault, showing the starting temperature point for your heating system's energy efficiency curve.

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

Navigate to the diagnostic menu using the display buttonsIdentify if the value needs adjusting based on your comfort levelsPress the menu or tick button to save the setting and exit back to the main screen

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Related fault codes

d.43View →d.47View →

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