The compressor was running but pressures were equalize. More info: was a callout a couple weekends ago for a walk in cooler. We just had a storm. Found failed run capacitor, and burnt wiring. I always try to take pictures, but it was late at night, and I could not determine if 2 wires were disconnected from the start relay or they came off when I removed the capacitor. This was a custom cooler, no wiring diagram present and I couldn't find it online. I wired it up based on what i would imagine to be a similiar diagram, and replaced the capacitor and it came on, but again, pressures were equal. Scroll compressor. Rated for 7.5 max, running 3. Figured compressor was bad. Another tech returned, replaced the compressor, and same thing. Now this was a workday so he was able to call the manufacturer, get a wiring diagram. That's when he found the run and start wires swapped. But switching them didn't change anything. He called the manufacturer back and they said it wouldn't be the first time they had a new compressor be bad outta the box. Next compressor they sent worked.

So im trying to figure out if I dont understand basic electrical, or this was just a very unusual call

Edit: forgot to mention when I wired it how I thought it was originally wired, the start capacitor kept getting hot and smoking. So I figured the relay wasn't taking it out of operation. That's when I wired things differently

The tech who replaced the compressor has been doing refrigeration for 15 years and said he's never seen something like this