What would cause my ac to work fine, then at about 190-200 degrees, no air out of vents. Shut truck off for a half hour or so and then all works great again. Fan blowing hard, air very cold . Blend and recirc flap both working

 

It sounds like your evaporator coil is freezing up. You are low on refrigerant. Either take it to an A/C shop for a proper check and fill or go to the parts store and get a DIY setup and put more refrigerant in.
Back to morning brew . . .