Well, the contactor fixed my short problem and apparently when it went it took out the transformer with it. So after chasing that down everything is kosher now except that the compressor won't come on. I'm getting my required voltage to the terminal plug at the compressor. Even knocked it with a 2X4 and hammer a few times. This makes no sense, seeing as the unit was put in last year. According to owner it had a freon leak and was shut off last fall. I thought maybe a capacitor, but it is dual and the cond fan runs just fine. Also has hard to start kit on it. Doesn't even TRY to hum or anything. Verified leak no pressure on system. Also no LP switches on diagram. Is it toast already? Asked owner to get his warranty papers together and call tech who installed it. I have condemned this thing. Am I missing something?

There is a continuity test that the service man will run at the compressor to make sure that the compressor is bad before he changes it out. It could also be the internal circuit protection but that would not make any difference it would still have to have the compressor changed.

You said that the unit was put in last year, I assume that you mean the complete unit and not just the compressor. But if it was the compressor and another one has gone out this fast I would think that the unit was not cleaned very well before changing the compressor last time.

The whole unit was put in, so I assume this could be covered under warranty. On the compressor ohm test, R to C and S to C? Do you just need a reading or a certain no. of ohms? It looks like maybe a 4 or 5 ton.

Does your volt meter beep on ohms? All we need to see is if it has continuity between all the terminals. You can try it again after it cools down it may have just been locked out on internal overload

That's the thing, it hasn't been hot enough to kick out on overload because I can't get it to run. The owner said he knew that it was leaking and shut the system down last fall when he noticed it wasn't cooling and hasn't run it since. Now maybe it cycled off too many times last year on overload? I don't have audible on my ohmmeter I believe I got 1 ohm from R to C and 2 ohms from S to C, maybe vice versa anyway it was 1 and 2 ohms. What I don't understand is no humming (lockedrotor) or anything. But I verified 245V at the compressor terminal plug(unplugged).

The owner is getting his warranty in order, as he should. I told him when he gets that worked out to let me install the unit this time. Thanks to everyone for their input.