It's been in the 90s for the past few weeks here in Maine, and we have no a/c, so currently we have 4 ceiling fans running non-stop, as well as 5 floor/desk fans. I am dreading my electric bill this month!! Normally, we only run the ceiling fans, once the temps get into the 80s and the humidity creeps up there. We live in a 120 year old house, and when it gets humid, if we don't keep air circulating, the house starts to smell musty. We've had it checked, there's no mold, the filters on everything are replaced on schedule, etc. It's just an old house with horsehair plaster/lathe walls throughout most of the rooms, and it just doesn't like humidity.