Right Compressor Installed?

If you have a rather old condenser, you more than likely had a piston compressor. They may have installed a scroll compressor, which is better. If you have the condenser model and compressor model numbers, I can tell you if it is a good match. A scroll compressor looks much different than a piston compressor.

The ZR21K is a scroll compressor - The original is a piston compressor. The scroll is a better design and should hold up better. Date code shows that compressor was made in March of 2021. So to answer your question, yes, that is a replacement compressor for your system. R407c, R438, R407a, R448, R449 can all be used in it. I'm sure there are a few others.