And we wonder why so many people get sick, all night in the AC, into the car AC, at work AC. Do you ever open your windows ? I live pretty deep in the woods and only had 1 bad pollen day, then the rain cleared that up. I haven't noticed my truck with pollen since. I don't know just prefer fresh air exchange until absolutely necessary to AC. Lower level of the house is 65 right now upper level 69 and it didn't cost me a penny