Low
S.05 on Vaillant Turbomax Plus 828

Your boiler is temporarily cooling itself down after use and should return to normal operation shortly.

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

Fan and pump over run (837/637 only)

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 5 to 10 minutes for the cooling cycle to completeEnsure your radiator valves are open to allow heat to dissipateIf the code persists for hours, try resetting the boiler

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