I am a mechanical Engineer. On the day The Tech showed up I was working on an industrial size AC design and calculation. I understand the systems. My home system displayed a high amp compressor cut-out. after thoroughly checking the system with my instruments, I determined it to be a worn compressor. The system would cool the house until the compressor shut-off. I purchased a compressor from my professional sources. My only concern was the silver brazing ability needed to install the new compressor. The tech nervously beat me to my home, called me on the phone and said my system was empty of very expensive R22 Freon. I asked him to find what must be a catastrophic leak, as we had used the system the previous day. He entered my house and disassembled my inside unit, which he said was leaking. HE LEFT MY UNITS DISASSEMBLED - pieces everywhere. HE STOLE MY EXPENSIVE R22 FREON AND LEFT. a major leak should leave trace oil - there was not a trace of oil at the hole (he made).