Low
S.17 on Vaillant ecoTEC plus System

Your boiler is simply finishing a safety cooling cycle after heating your water and is performing exactly as it should.

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

DHW mode: Pump overrun

Engineer required

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

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