Low
S.34 on Vaillant ecoFIT Pure 412

Your boiler is temporarily running its pump to prevent the internal pipes from freezing, which is a normal protective feature during very cold weather.

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

Frost protection active

From this model's manual
Verified against the Vaillant Ecofit Pure 412 installation & service manual, page 29.
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 the display returns to normal once the surrounding temperature risesEnsure your heating controls are set to a comfortable level and not turned off completelyKeep the boiler cupboard door open slightly if it is located in an unheated space

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S.30View →S.31View →

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