Low
S.17 on Vaillant ecoTEC

Your boiler is currently running its internal pump to move residual heat out of the system, which is a normal part of the cooling-down process before it switches off.

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 over run

Engineer required

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

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