Has Anyone Built a Mini AC Using a Fridge Compressor?

You could also look into building a swamp cooler; they might be more effective for your needs.

Interesting idea! I was actually considering something similar but with parts from a semi-truck. I want to help someone in a very hot region with solar power. However, I think a mini split AC might be easier, especially since some models work on DC.

A fridge compressor just won't cut it; it takes way too long to cool down a fridge from room temperature. You'd hardly feel any cooling from just blowing air over the coils.

Do you have the necessary vacuum equipment to manage this setup? You’d need it to properly service the system if you attempt it.

Those small fridges usually use peltier cooling instead of a traditional AC compressor, which isn’t efficient and really can’t cool down a room effectively. You have to vent the heat too, or you'll just heat up the space you're trying to cool. If you use a larger fridge compressor, you're basically building a DIY window AC, which is complicated because AC systems need to be sealed and serviced with special tools. Honestly, just buying a $125 window AC unit would be way easier and cheaper than this project.

Honestly, trying this is a bad idea. The energy efficiency loss would be huge compared to a real heat pump. It's just not worth the effort for the output you'd get.