Low
d.10 on Vaillant Home System

Your boiler is simply showing whether its internal water pump is currently running or resting.

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

Status of the internal pump in the heating circuit: off/on

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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Related fault codes

d.01View →d.02View →d.11View →

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