To preface, we had the system purged and recharged a few months ago by my neighbor (he is a certifed AC tech who fully evacuated the system and charged it by weight) when the 134a charge was low. AC has worked great since.

What is happening now is after about 15-20 minutes of operation nearly no airflow comes out of any vents, no matter what position the vent select knob is in. You can hear the fan laboring away, trying to push air through a blocked climate control system. This happens even when cold out and heat is flowing through the system.

I have found that if I turn the AC switch "off" normal air flow vent control resumes in about 5 minutes (or less). If I turn AC back "on" it works fine again for another 10-15 minutes, and then the airflow becomes blocked.

At no point do the AC and/or Recirc lights flash indicating an error condition. I have not yet run any error codes, but that will be my next step I suppose.

Is it possible that the AC is running incorrectly and frosting up the evaporator to the point no air flow can pass through?

Any and all help, tips, and advice will be greatly appreceated.