[theoreticalmal]

I always wondered how difficult it was to do this. I’m really glad to know it’s possible

[mothballed]

Getting the 608 is mostly rote memorization and the only thing required at the federal level. On the state level if you want a trade license that generally takes 4 years, but where I live residential owner-builder doesn't need it.

[brianwawok]

608 lets you buy the refrigerant