Low
d.19 on Vaillant ecoTEC plus System

This code is simply an information display showing the current operating setting of your boiler's internal pump, rather than an error or 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

Pump operating mode, 2 stage pump: 0=Burner mode stage 2, pump flow/overrun stage 1; 1=Heating mode and pump flow/overrun stage 1, hot water handling mode stage 2; 2=Automatic heating mode, pump flow/overrun stage 1, hot water handling mode stage 2; 3=Stage 2

Engineer required

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

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