Conversion from R22/R134a to newer gas types

[iec]

Has anyone converted a system from R22 or R134a to any of the newer type of gas based system?
if yes kindly indicate experience & process followed...thx

[a/c.nick]

yes we have done one unit. recover old gas flush with o.f nitro ,vac and recharge with mo99 or r-438a. we have found the the system wont heat as high as r22.