I have a duo therm rooftop ac unit that is not working. The fan kicks in, but the compressor doesn't seem to even try to kick in. I'm assuming that I am going to have to replace the unit, but is there...
It's done using a volt meter starting at the common(black) lead on the top of the compressor. The voltage is measured to ground or actually, anything metal on the unit. If you're not familiar with electrical troubleshooting, it's best to have a tech do it. My point was, systematic troubleshooting works a lot batter than throwing parts at it based on a recommendation from someone who may not know as much as you do about it. A lot of stuff gets parroted here just for the sake of a post.