Low
S.13 on Vaillant Turbomax Plus 828

Your boiler is currently trying to light the flame to provide hot water, but it has not quite finished the process yet.

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

Ignition sequence (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

Check if hot water is being delivered to your tapsMonitor the display to see if it changes to a heating code (e.g. S.14)No action is required as this is a normal status message

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S.11View →S.14View →F.28View →F.29View →

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