2002 Ford Escape A/C

Air Conditioning problem
2002 Ford Escape

My 2002 Escape is intermittenly blowing extremely hot air, like the heat is on, when the A/C is turned on. I have taken my car to a repair shop and had the compressor replaced twice, orifice tube replaced twice, condenser replaced three times, and clutch cycling switch and receiver dryer replaced once. The dealer now has my car and can't find anything wrong. The A/C works fine in the mornings. In the afternoon, it blows out heat. I can cut it off and on but it will continue to blow heat each time. In the morning after it's sat all night, it works. Any idea what could be wrong?