How to wire up a PSC motor from a air conditioning unit?
You probably have the common terminal identified correctly, but you could be right or wrong with S &amp; R. It may be that the S &amp; R windings are identical and you connect the capacitor to either to select direction of rotation.
The motor may be a &quot;universal replacement&quot; that is designed to replace motors on a variety of products. If you know which way it is supposed to turn, take a guess at S &amp; R and connect it to power without installing it. Hook it up through a switch and switch on very briefly. If it turns the right direction, your guess is right. Then turn it on and check the current. If you know the rated current, you can compare with that. No-load current could be 30 to 50 percent of rated current, so that doesn't tell you very much, but if the current is more than 60 percent of rated, I would be worried.
Install the motor if it seems ok, double check that the direction of rotation is right and check the current both immediately after start and after the compressor has warmed up.