Ayuda

For efficiency you want the filter to be the correct size or larger so it does not create back pressure which hurts the fan's output. For example, I am using a 4" (100mm) fan with a 6" (150mm) carbon filter but I never use a smaller filter.

Hi. You can do that but you need to make sure the carbon filters m3/h is higher then the fans otherwise you will be sucking smells out. Eg. If filter is 300m3/h and fan is 200m3/h your fine but if filter is 300m3/h and fan is 400m3/h then the filter won't work as it should. Hope this helps.