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.

Technical description

Pump over run (hot water operation)

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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Related fault codes

S.07View →S.10View →S.14View →

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