Quote Originally Posted by freonjoe View Post
If someone shows up at my shop, I will recover them for free as long as the cases are off. Sometimes I just buy them outright for .15 a pound. As far as the refrigerants having value, R11, R12 and R22 are worthwhile to recover and sell. R134 and R410 aren't worth shipping. That includes all the blends as well. IE 401 A & B, 402 A & B, etc. I think all the blends start with a 4 except 502 if I remember right.
There are actually 13 blends that start with a 5 according to the document at the attached link:

List of refrigerants - Wikipedia, the free encyclopedia



Personally, I have run into R-500 and R-502B