of R-22 and R-125 with hydrocarbon R-290 (propane) included
to improve mineral oil compatibility. This blend is formulated
to match R-502 in evaporator temperature ranges and does not
significantly increase discharge temperature in R-502 retrofit
situations. Discharge pressure, however, can increase from
25 to 40 psi over pressures seen with R-502. Although the propane
was added to improve oil circulation it is still recommended
that some mineral oil be removed and replaced with alkylbenzene.