Low
d.05 on Vaillant Home System

Your boiler is simply displaying the target temperature it is currently trying to reach for your heating, which is a normal status message rather than an actual 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

Determined heating flow set target temperature: Current value

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

Press the 'Back' or 'Menu' button to return to the main displayCheck that your external thermostat is calling for heat if you want the temperature to increaseNo action is required as this is an information code, not an error

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d.00View →d.09View →S.04View →

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