Went riding in Missouri last weekend.  Pulled up and plugged in.  The rooftop would not start.  No fan, no anything.  Checked the breaker and the wiring going into the switch.  All seemed in order.  Banged on it.  Nothing. Everytime I went into the trailer, I tried it.  Nothing.  The next day I was standing outside and I heard it start up.  The wife had a cabinet door slam and it started running.  It would run a while, then stop.  Just slam the door and it would start again.  Went riding this weekend.  It ran fine for the first day, then stopped.  No slamming, shouting, screaming or banging would start it.  Drove home plugged it in, nothing.  Any suggestions?

Hello Tim ...

There's either of two problems.  The compressor has a problem.  When it overheats, a thermal cut-off switch opens.  When it cools, the unit runs again.  More likely, there is a loose connection somewhere.  By your question, I'd suggest you take it to a competent shop to trace the circuit.  It will have to be opened, and there's a bunch of things that could hurt someone.

No disgrace in lack of knowledge or test equipment, but it will hurt to find its limits.

Do you know what a starting capacitor looks like.  You can inspect it yourself.  If you have a meter you can also check to see if it charges and discharges.  If you can find it if the can looks swollen then it is no doubt bad.  If you were closer I would come look at it for you.  Any heating and air conditioning supply house would have the cap or be able to order it.  I have heard of some Heating and air conditioning people charging $125 dollars for the cap and $125 for the labor.  Job takes about 5 minutes and the part cost as I said $15 to $25 dollars. It's worth checking out.