So, in this thread I was asking about whole house fans https://boards.straightdope.com/sdmb/showthread.php?t=858958, but after reading a lot of the comments I started looking at info online about cooling the house with window fans. Sites like this one: https://www.bobvila.com/articles/how-to-use-a-window-fan/ say to have an equal number of fans blowing into the house as you have blowing out.
I was wondering exactly why that is the case. With a whole house fan, you simply rely on the open windows to bring the cool air in. Is it simply because window fans are not likely to be a powerful as a whole house fan? But if I prop this fan, https://smile.amazon.com/gp/product/B06XGSJ94B/ref=ox_sc_act_title_1?smid=AF8EGQ3KRZQB6&psc=1 with its 2400 CFM (about the same size as the whole house fan I was looking at) in an upstairs window, wouldn’t it be almost as good as the whole house fan?
I currently have two small twin 6 inch window fans that move little air, and I have also started to prop a box fan in an upstairs window blowing out as well. It helps, but it doesn’t cool the rooms as much as I’d like (I have several digital thermometers that display indoor and outdoor temp throughout the house).
And do you think it would make a great difference if I were to put the fans in the top of the double hung windows (which would involve either ordering a bug screen that covers the full height of the windows or working out a way to get the existing screens to seal the top pane when opened)?