Supply air. Return air. Enough said.
It still amazes me to see things like this I used to work on a lot of strip malls small shops that had no indoor room for a split system they would mount a roof top on a curb that had the supply and return in the same opening at the ceiling and they were always freezing the coil had to change the filter about every two weeks and nothing but complaints from the renters:roll:
Wow!
You need to save that one[FONT=Tahoma][size=2]!
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