Low
d.45 on Vaillant ecoFIT Pure 835

This is a settings menu display showing the starting temperature for your heating system, rather than a physical fault with the boiler.

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.

Technical description

Value for the base point of the heating curve

DIY fix possible

Press the 'Back' or 'Menu' button to exit the diagnostic settingsRestart the boiler using the power button if the screen remains stuckConsult your manual if you intended to change the weather compensation settings

Find a Gas Safe engineer
Search the official register →

Related fault codes

d.43View →d.47View →

Related guides you might find useful

Is boiler cover worth it?

Break-even maths on monthly cover.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →

New boiler cost 2026

Realistic UK prices for a swap.

Read →