Mi Air Purifier Pro H Manuel D'utilisation page 5

Note
For your better user experience, it is recommended to replace
the filter every 10-14 months. When the service life of filter is
due, please replace it in time.
When the filter is saturated by harmful gases, it may give off
odors. It is recommended to store the filter in a sunny and
ventilated place to eliminate odors, so that it can improve the
activated carbon and restore dust adsorption capacity.
Illustrations of the product, accessories, and user interface
in this user manual are for reference only. The actual product
and functions may vary due to product enhancements.
If different model of filter is selected, the effect of purification
may slightly differ.
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