Low
d.43 on Vaillant ecoTEC plus System

This code is simply an information display showing the current heater setting level, not an error or a sign that your boiler is broken.

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 curve: 0.2 to 4

DIY fix possible

No action is required as this is a setting display, not a fault.

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