Low
d.00 on Vaillant ecoTEC Plus 625

Your boiler is simply displaying a status message telling you it is automatically adjusting its power output to best heat your home, rather than indicating a 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.

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

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

d.01View →

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