Low
d.43 on Vaillant ecoTEC Plus 938

This code is simply an information display showing the current setting used to manage how much heat your radiators produce based on the outdoor temperature.

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

Engineer required

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

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