R22 to R421A Conversion

[LG63]

A search of GJ brought up exactly two threads containing the term R421A………I’m guessing it’s not a popular conversion. Is it just not cost effective?

 

[Ohmthis]

421a is a pretty popular conversion, no parts to change and is very close to r22. I think it's carbon foot print is pretty high for a replacement refrigerant. Some people fear it will be phased out too and just start the process again. Around here r407c is the most popular replacement. In all honesty, unless your system is pretty new and you have to reclaim because of a coil replacement I couldn't justify the cost of replacement. Why are you asking?

 

[magicrat]

another 10 years and the r22 system will have gone the way of the dinosaur.....I have seen some of my hack friends top off and just pump down a system and put the new **** in....I wouldnt do it but it did work when i saw them do it

 

[stikman56]

I'm told the issue with these "replacements" for R22 is when it leaks out, you can't just put more in and expect it to work right again. The balance is off because one ingredient of it is what leaks out, leaving it off balance, so unless you drain it and start over, it's useless at that point.

 

[Ohmthis]

I'm told the issue with these "replacements" for R22 is when it leaks out, you can't just put more in and expect it to work right again. The balance is off because one ingredient of it is what leaks out, leaving it off balance, so unless you drain it and start over, it's useless at that point.

It's not just with "replacements" either. Our beloved r410a is a mixture and when leaked there is a fractionation of the blend. R134a is the same. I'm going to link to a list of "replacements" and pros and cons of them. If you look at several of the graphs, r407c closely mimics r22 and is also the least to affect the ozone.

https://www.epa.gov/sites/production/files/documents/Choosing_Right_R22_Retrofit.pdf

 

[LG63]

Why are you asking?

I’m going to have the condenser moved and the line set will be replaced in the process. The system is in good shape so it could go another 5-10 years and I thought by going R421A I could count on it being available (at a reasonable price) during that time period.

I was told by one company that R421A could be used to top off an R22 system but I can’t seem to find much to support that online.

 

[theoldwizard1]

another 10 years and the r22 system will have gone the way of the dinosaur.....

Run what you have for as long as you can and then replace the whole system.

 

[Brian_WK]

It's not just with "replacements" either. Our beloved r410a is a mixture and when leaked there is a fractionation of the blend. R134a is the same. I'm going to link to a list of "replacements" and pros and cons of them. If you look at several of the graphs, r407c closely mimics r22 and is also the least to affect the ozone.

https://www.epa.gov/sites/production/files/documents/Choosing_Right_R22_Retrofit.pdf

R-410a is a near-azeotropic refrigerant and should be charged as a liquid and no top offs. R-134a is azetropic and can be charged liquid or vapor and can be topped off. But in either case if you have a leak it should be fixed and properly recharged.
Almost all refrigerants are a blend as long as the boiling points of the refrigerants are close they can be topped off but as I stated earlier it should be fixed correctly anyways.

Brian

 

[Ohmthis]

I’m going to have the condenser moved and the line set will be replaced in the process. The system is in good shape so it could go another 5-10 years and I thought by going R421A I could count on it being available (at a reasonable price) during that time period.

I was told by one company that R421A could be used to top off an R22 system but I can’t seem to find much to support that online.

I don't see that as a good reason to switch. The company told you wrong. There is no direct (EPA approved) drop in for R 22. You should ask for a bid to convert to another refrigerant and see how much it costs. Please read the pdf that I linked if you are serious about a change, it is very informative. Do your research so you can ask educated questions and call BS to some of the answers.

 

[zmaxmotorsports]

I'm told the issue with these "replacements" for R22 is when it leaks out, you can't just put more in and expect it to work right again. The balance is off because one ingredient of it is what leaks out, leaving it off balance, so unless you drain it and start over, it's useless at that point.

That's why you fix the leaks 1st.