Question about window fan?

Question

Please settle an argument: My sister says when you put a box fan in a window you make it blow in. I say that just sucks the bugs in. I used to have one and we had it blow out. It still moved the air through the house, but we didn't deal with bugs. She refuses to believe that will still work.

Answer 1

If bllowing the HOT air out of the house is your goal...It would need to face out.

Answer 2

It's a simple matter of turning the fan around.  It will either blow out or in.  If you have a screened window, bugs should not be a problem.

If you have the fan blowing out, another window in the house will need to be opened so the air can pass through.

Answer 3

Blowing out seems sensible. In these green days you obviously want a heat exchanger though :-)