Air cond ?

i have a buddy who set up is something like this in a garage

will he have any problems putting a window ac unit in wall and exhausting in garage

room is in a add on and there are 2 doors between grow room and main section of garage

crappy pic of said room

yeah as long as that air can eventually exhaust to the outside, because the air that shoots out the back of the a/C is hot air......only thing i'm thinking if his garage would get hot