Low
d.41 on Vaillant ecoFIT Pure 435

Your boiler is displaying the current temperature of the water returning from your radiators rather than showing an error; this is an informational status code and not 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

Heating return temperature

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

Check if the display returns to the main temperature screen after a few momentsPress the 'back' or 'menu' button to exit the diagnostic information if you accidentally selected itNo action is required as this is a normal reading of the system's return water temperature

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