Low
S.17 on Vaillant Turbomax Plus 828

Your boiler is temporarily running the pump to cool itself down after you have used the hot water.

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.

What the manual says

Manufacturer manual

Pump over run (hot water operation)

From this model's manual
Verified against the Vaillant Turbomax Plus 824 828e installation & service manual, page 38.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait for the code to clear automatically as it is a normal status messageEnsure your radiator valves (TRVs) are open to allow heat dissipationCheck that the boiler pressure is between 1 and 1.5 bar on the gauge

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