Low
d.19 on Vaillant Home System

Your boiler is displaying a status message about how your internal pump is currently configured to run, rather than a dangerous 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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Related fault codes

d.01View →d.18View →d.22View →

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