Mix, replace R22

[learner]

Hey everyone :)
this is Learner.. currently in Bulgaria :)
My parents have been importing heat pumps for several years now. The HPs use R 22.
Can we discharge it - R22 - and replace it with
R 417?
can we mix R22 with R 407 ?
thank you for your help!
have a peaceful day!
Learner

[The MG Pony]

firstly you NEVER discharge R-22 to the air, have it recovered. Secondly R-290 is a replacment for R-22 that offers some good benifits, but it must be used by only trained peoples as it can be verry dangerous if poorly don.

The system must be solid and leak free, it must be well vacuumed (500 microns or better) this is true for any refrigerant!

R-290 (Propane) is a nice low energy consuming refrigerant that is safe for our air!

[Brian_UK]

Yes you can replace R22 with R417a but you cannot mix refrigerants.

[jure]

you cant mix refrigerants but
by my experience you can fill R22 into R407C sistems but just about 10%, but you cant fill R407C into R22 sistems