Low
d.45 on Vaillant Home System

Your boiler is notifying you of a specific setting adjustment related to how it calculates the temperature needed for your radiators based on the weather.

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: 15 to 30

From this model's manual
Verified against the Vaillant Home System installation & service manual.
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 installer level settings menu (if you have the manual)Locate parameter d.45Adjust the base point value to your preference between 15 and 30Save the setting and exit the menu

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Related fault codes

d.43View →d.47View →

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