Ok guys and gals... I KNOW it ain't right or what's taught or what they say ain't comtatible (so they say) HOWEVER!
I have come across units that have been marked by passed tech's "R-12/134A/409/hotshot.mix. And are working fine after I repaired a small leak and partially recharged with what I had on hand (134a).
I've also used R22 instead of 404a to get a WI freezer running after fixing a leak, havn't had to go back in 6 months and used 3lbs on a 8lb system.
The equipment,refrigerant,oil and other manufacturers adamantly proclaim that they WON'T mix but they will.
Now before you get your panties in a bunch! I don't do this all the time as a general practice, but only in a pinch. If the system pulls down to temp. then I leave it at that.
you can get as technical as you want but, R12,134a,409,hotshot,and a few others ALL have REALY close head pressure.. and the bottom line is protecting the compressor. R 502,404a,r22...ect are the same.
NO they are not intercomtatible with P.O.E. oil and Mineral oil. I know this but if it's a mix then as long as the majority is oil compatible it will work. Reduce performance and life???? maybe.
My proof I recently came across a 1 door upright freezer that was to be scrapped,marked 404a, The comp. worked so I fixed the evap. leaks and weighed in the 16 oz charge of as equal parts I could of 134a,404a,22,409a.
and also some recovered witches brew
Well it reached -10 F in 45 min. from 80 F.
Now let the beatings begin. (no I didn't make this up to provoke you guys...)