Low
d.41 on Vaillant ecoFIT Pure 425

Your boiler is displaying the temperature of the water returning from your radiators to help you monitor its efficiency.

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

No action is required as this is an information code rather than a fault.Press the 'back' or 'menu' button to return to the standard pressure or temperature display.Observe if the return temperature is significantly lower than the flow temperature to ensure your system is balanced.

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