I will confirm what PNUTMNM said. I just recently noticed this on a trip. I had the defroster on for most of the trip (mostly by accident) and noticed that it was definitely becoming pretty cold inside, I knew that the defroster uses the AC, so I switched it to regular a non defrost selection and it was still very cold... well I stopped for something to eat, got back in and the air was now coming out warm and humid, so I just rolled down the windows (my preferred cooling method).