1996 a/c problem

[detforme]

I had been having this problem for sometime now, and found that a line had a hole burned in it. I replaced the line. I had already put a new compressor exp. valve, and drier in. So it got vacumed and filled gy weight. Problem sovled. well it seems as though the problem is back. It seems like it normally happens when the car is very hot from being outside in the sun. I turn the a/c on an it will blow cool at first and then go warm. I figured it was freezing up, when you feel the line coming out of the evaporator the high line is fairly cool and the low warm, but the high side from the compressor to the condensor is very hot. If I continue to drive with the a/c off for a little while then turn it back on it will work fine. Please help!! its driving me insane. thanks

update:I checked the pressures today. when the a/c is not working correctly i.e.-the drier and high lines after the condensor are cold; the pressures are 33 and 80. When the a/c is functioning correctly 33 and 175 at 85 ambient, which is within factory spec. Another thing is that i only seem to be able to get it to work correctly when i shut the blower motor completly off and let it sit, if i just turn the compressor off it will not work correctly.