Low of refrigerant R134. Coils or cabin filter (if equipped) can also be clogged, blocking airflow, which will cause unit to ice over and block air flow. Have the refrigerant charge checked by a pro.
No, he did not. This idea comes from the book, "The Pushcart War," which is actually a work of fiction (although the author,Jean Merrill. imaginatively and cleverly makes it seem like a work of historical fact.)