Low Information
D.000 on Vaillant ecoTEC Plus 65

Your boiler is currently set to run at a lower power level than its maximum capacity to save energy or match your home's heat demand.

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

Partial heat load (Diagnostics menu)

What causes this fault?

This status appears because the boiler’s maximum output has been manually limited during installation or a service to better suit the size of your property. It is not a mechanical failure, but rather a configuration setting that ensures the unit doesn't use more gas than necessary to heat your radiators. It prevents the system from 'short cycling,' which occurs when a boiler is too powerful for the home it is heating.

DIY fix possible

Press the 'Menu' button on the control panelNavigate to the diagnostics settings (D.00) using the +/- buttonsReview if the output kW matches your home's requirements, but usually, this setting should be left to a professional during installation

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