Low
d.11 on Vaillant ecoTEC plus System

Your boiler is simply performing a routine check on its internal water pump to ensure heat is moving around your system correctly.

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 heating circuit's shunt pump: off/on

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.10View →

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