BillsE500

Book says it "reduces bad odors and removes pollutants".....so wouldn't I want this on the whole time. Why ever switch it off? I understand if stuck in traffic next to dead skunk I'd switch it off and go with recirculation mode. But in general seems like I'd always want the charcoal filter option on??

apl175

Because the activated charcoal factor has only a limited (but numerous) number of binding sites that organic chemicals can bind to. By running air through the filter all the time, you decrease the life of the filter, and the ability of it to adsorb chemical contaminants when you really need it.

BillsE500

How often would I change those filters under "normal" usage.

JoeNobody

replacement of filters is done during one of the regular scheduled maintenance.