Ford Repair: 96 E350 AC running at low performance, ac hoses, controller circuit

Question
96 E350 15 pass clubwagon, 138K miles on 5.8L v8 gas engine.
Air still blow, but not cool, just a little below the outside temp. Checked freon pressure normal. But noticed that the compressor only keep running 3-5 minutes. after than it running 5-10 seconds with 5-10 second idle, not sure if that's normal. If not, is it a compressor problem or the controller circuit problem.

Thanks for any suggestion,
Joe

Answer
A vehicle ac system canhave what looks like normal pressures and still be low on freon. The only true method to know if the system is at the correct charge is to evacuate and recharge. Your van most likely has rear ac, which takes more freon than a front system alone.

Check the ac hoses, see if you have an area that is freezing up. Check the cycling switch, they will sometimes cycle too fast when failing. Normal high and low pressures depend a lot on ambient air temp and humidity. Just because the pressures look normal does not necessarily mean it is charged correctly.