Low
S.04 on Vaillant ecoFIT Pure 825

Your boiler is operating normally and is currently heating your home.

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

The product is working correctly (Heating mode)

DIY fix possible

No action is required as this is a standard operational status message, not a fault.

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