Also, it can take a few minutes for a new capacitor to charge up and power on the A/C unit after a swap. I learned that the hard way.
My A/C went out at the end of last summer. I researched and read it could be the cap. Located the cap on the outside unit. It was swollen so I bought a new one and installed it myself. Turned on the A/C and nothing happened. Fan still wasn't blowing.
I was afraid I was about to burn up the whole unit, so I turned it off quickly and called an A/C company. They sent out a guy on a Saturday (extra fee). He came out, tested it, looked confused and said he thought I needed a new fan motor. He put in the new motor, turned on the unit and nothing happened, just like when I had turned it on after putting in the new cap. A/C guy says "Sometimes it takes a few minutes to power back up." He left it on, and sure enough, a couple minutes later it powered up and started blowing.
Looking back, I'm almost positive I fixed it with the $12 capacitor, but unnecessarily paid for a new $500 fan motor because I didn't let the cap charge up long enough.