Low
d.00 on Vaillant Home System

This is a configuration setting that shows the boiler is automatically calculating the most efficient power level needed to heat your home.

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

Heating maximum output: The maximum heating output varies depending on the product. Automatic: Unit automatically adjusts the maximum output to the current system demand

DIY fix possible

No action is required as this is an advisory status code, not a failure.If you wish to limit the maximum power manually, you can navigate the installer level menu to change 'Auto' to a specific kilowatt value.Monitor your radiators to ensure they are reaching the desired temperature.

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Related fault codes

d.01View →d.02View →

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