2016 U max a/c very dissatisfied.

So the last few days I was camping for the first time in hot weather. (Upper 80's) I figured I would be fine but the a/c was not up to the job. I have the floor mounted a/c Friedrich model. The a/c would run for a few minutes then the compressor would shut off blowing only hot air. After doing a search on the forums this seems to be common. It sounds like the compressor shuts off because the unit over heats or doesn't vent well. I have not found a thread that appears to fix the issue on the floor mounted T@bs.
 This is an idea I had but I really don't know if it would work. So I'm looking for feedback on this. I was thinking of placing a box fan on the outside of the T@B with the back of the fan against the trailer. The fan I'm thinking of is about the same size as the metal vent cover. My thought is the fan might draw enough heat out of the box the a/c unit sits in preventing it from over heating. Anyone try this or is my idea flawed?