I have an attic fan as well. I have used it a few times on very hot nights but it is VERY noisy so I would rather use a stand fan.
I’m not a big heating user – maybe 5-6 wks. a year, nights only (partial) so this is the reason I can change the heat register filters infrequently. Yes, I do have thick carpet and long drapes and pets but I am religious about keeping up after them. I would like to extend my hardwood floor to the rest of the house but this would cost $4400 for my living room alone. I almost have enough leftover HW slats to do the hallway, however, so that will be the first carpet to go.
Note: My house has very thick insulation installed above, on the sides and beneath it and double-paned (1 triple-pane) windows throughout. This keeps my utils to just above baseline when the heat is not running.
