All I know is that it will do whatever is necessary to achieve and then maintain a set temp. If it thinks another notch of fan speed will do the trick, it does it. It will go into recirc by itself when ambient is over 85, I think?

I never use auto- would rather run AC in recirc on low fan speed all the time, the few times I do use it. I prefer having all 4 windows cracked an inch or so when on the hwy.