Low
S.17 on Vaillant ecoTEC plus aquaPLUS

Your boiler is temporarily running the pump to move excess heat away from the hot water heat exchanger after use.

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 Ecotec Plus Aquaplus 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 up to 20 minutes for the status code to change naturallyEnsure radiators are not all turned off at their valvesCheck that the boiler pressure gauge is between 1 and 1.5 bar

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