I’ve got a R22 Medium Temp Walk-In Cooler running on R407c and 15-20% POE oil.

Plus is 15-20 years old as well.

Also, retrofitting should be considered system specific.

R407c is the recommended for R22 with the closest operating pressures and smallest efficiency drop compared to R422b. The following is a set of general guidelines to assist in the replacement of R22 condensing units with equivalent R407C units. Our R422d refrigerant is a true drop-in replacement and no system changes are required. Has anyone heard of people putting 407 on top of 22? The bottom line is: If your system lost more that 15-20% of the total R22 charge you may want to consider to evacuate (with a recovery unit) the residual gas and recharge with a replacement. The guys I've been talking to are using the M099, but the system should be recovered and emptied of all the R22 for a different reason. R407c has been billed as one of several drop in replacement refrigerants for R22. Don`t worry about oil changes and rest assured R422d refrigerant is good for cap tubes and TXV. It is also used in medium temperature refrigeration systems. Has a Receiver and headmaster and has been running with no issues for a couple years now. The choices are to top off with R22 or recover the R22 and replace with R422b or R407c. A licensed professional should be contracted to completely remove the R-22 … Arkema Inc. does not advocate the use of the term “drop in” as we believe the term implies a technician can just “drop” the refrigerant into an R22 system without doing any other work. Below you can find different R22 replacement refrigerants and the+/- of each. It is not recommended to drop R-407C into R-22 systems on top of the existing charge in cases of low refrigerant levels. Any time you mix refrigerants you are making a new refrigerant. Substitution of R22 for R407C. As per Montreal Protocol, R22 is going to be phase out due to its unfavourable impacts related to environment e.g. I am told that it is "ok" to mix the two. Converting R22 Systems to R407C. Servicing of refrigeration systems. Its molecular weight and critical pressure and boiling point, with other criteria are very very close. All new compressors use POE oil and are compatible with R407c and most other R22 replacement refrigerants. R407c is the recommended for R22 with the closest operating pressures and smallest efficiency drop compared to R422b. So I am at the parts house chatting with other techs about the price R22 and I come to find out that there are some techs that are no longer buying R22 and just adding 407C to R22 systems that are low on charged. One of the fellas at the parts house was trying to convince me that 407C on top of R-22 was a good idea. R-407C can be used to retrofit existing R-22 systems in positive displacement, direct expansion refrigeration and air conditioning equipment. I dont use 407c I use R422D as drop in, no need to change oil., just need to fix leak, vacuum. R-407C should not be used in centrifugal chillers or other equipment that uses a flooded evaporator due to its high temperature glide. We've been recovering all the 22, making necessary repairs and then replacing with 407. So I am at the parts house chatting with other techs about the price R22 and I come to find out that there are some techs that are no longer buying R22 and just adding 407C to R22 systems that are low on charged. Arkema Inc. does not advocate the use of the term "drop in" as we believe the term implies a technician can just “drop” the refrigerant into an R22 system without doing any other work. procedures using Honeywell Genetron ® 407C and Genetron ® 422D. They are not meant to replace any existing relevant standards or recommended good practice. Any time you mix refrigerants you are making a new refrigerant. There are "drop-in" R22 replacement in the market like R421a, R422B and MO99 (also MO29 for low-temp applications) but NONE of those can be mixed with R22.