"Julie P." wrote in message
...
1) Do window A/C units, when set on the fan only setting, blow fresh air
in from the outside, like a regular box window fan, or recirculate air
from the inside?

Inside air. Even the ones with a vent onlybring in a tiny amount of fresh
air. I was told by one of the engineers at a major AC maker we suppliied
that "it is a selling point".


2) Same question, but with the A/C turned on. Does the air come from the
outside or inside?

Same answer

Because I have my window A/C set to fan only, and even though it was
freezing outside, it was blowing warm air!

Yes, that is a problem with window AC if you have only one window in the
room. Aside from taking it out, no easy way to get fresh air inside.