cooling system

Last winter I experienced a couple supercharger sessions when the radiator fan ran at maximum speed as my charge limit was reached - but no airflow through radiator opening (below front bumper). I could see that the active shutter was closed while the fan ran like a jet engine. It was cold out...

I was driving to work today, and suddenly the vent started blowing hot air. Not warm, hot. The rheostat was turned all the way to the cool side (eg, the heat was not on). Pushing the AC button didn't help. Turning off the fan didn't really help, hot air was till coming up, with a bit of an...