I just had my ac recharged at the dealer, and they put a fluorescent in, and no signs of leakage.

It runs for quite a while (an hour?) then, the compressor just shuts off. The air blowing out smells like a humid day in Miami. And the ac stays off until I let it "cool" for an hour.

Is there a temperature cutout sensor? Maybe mine is bad?

What could explain this erratic behavior?

Can I fix this myself?

Had exactly the same issue with my AC and the "bread bag clip" fix worked great. Has been running fine for over three months.

I would concentrate more on the compressor clutch gap. If the AC cuts out, check the clutch, very carefully, with a broom stick. If it engages with a very light tap, then you need to have the clutch reshimmed.

Klaus
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The more I learn, the more I forget. So why learn?

Where do you tap it? I don't know where the clutch gap is.

The AC clutch is by the left front fender, driven by the serpentine belt. There is very little room and lots of spinning things, so be extremely careful not to touch any other moving thing. The clutch is way down low and will not be spinning if the AC is not working.
A light tap directly in the center of the clutch is what is needed to do the test. A mechanic will lower the air guide under the front of the car and tap the clutch with the plastic end of a long screwdriver from underneath. He will also check the gap for verification.
If you do a search on AC clutch, you may find out how to fix it yourself with some bread bag clips and a little glue.

Klaus
--
The more I learn, the more I forget. So why learn?