Low
d.14 on Vaillant ecoTEC plus System

This code is simply an information display showing the current speed setting of your heating system's water pump, rather than a sign of 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

Operating mode of the modulating pump: 0=variable rotational speed (auto), 1;2;3;4;5=Fixed rotational speeds

Engineer required

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

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