R502 info

[Fhqwhgads6680]

Hello guys, I am working on a single stage that I just finished, and was curious what the differences were between R502 and R22. I know that R502 is part R22, so I assume it still uses mineral oil? Is 502 the best refrigereant I can upgrade to without having to cut out the compressor and change the oil or is there one better, or can R502 be blended with something else for better temps?

Thanks,
Brandon

[Gray Mole]

I don't know if 502 is banned from use in the US or not yet.

I know it's been banned for use here. Some countries are still ok to use it.

It's a good gas though, nice temps and load holding.

If you want to stick to mineral oil, you've got R22, 502, and 402a to choose from easily and likely a few others I'm forgetting, 402a being the coldest of them.

Gray

[Fhqwhgads6680]

Ahh thats must be why I don't see it used often. I saw that Ssilencer was using it ans was just curious since it is part R22. I didn't realize that R402a was mincible in mineral oil tho... How is it at holding load compared to other refrigerants that use POE? Also how much would blending R22 with R290 improve temps? or would 402a be better?

[Gray Mole]

Yeah, I'm pretty sure that a lot of the south american countries can still use it for a while but it's being phased out everywhere.

Currently 402a is about the coldest and best capacity for single stage without getting too creative. You can blend in isceon 89 or R410 or whatever but if you just want to keep it simple, just 402a is good.

It runs a little hotter and harder than other refrigerants, so high fan speeds, or larger condensors or adding a desuperheat coil is a must to get it to work nice, but the results are quite good.

For a quieter system or smaller condensor etc, either 404a or a R22/290 blend is really good too.

But yeah, mineral or AB oil is good for 402a. AB is recommended but I've used with mineral no problem. You can get it to work with Ester as well, but I like to add a touch more 290 to it to make sure the oil travels nice.

507 is good and all that, but for the little extra work and thought to get 402a to work in a single stage I think it's worth the effort. If you use mineral oil then it's just easier to go with 402a.

Gray

[Fhqwhgads6680]

Cool. thanks for the info! now im gonna have to get a hold of some of that...
Also just curious, but do you know where I can find a pressure chart for 402a for charging? also will I have to get new gauges? the ones my dad has are for 12, 22, and 502. Thanks!

[Gray Mole]

http://www.uri.com/is-bin/intershop.static/WFS/PrcTransaction/-/en_US/catalog/ptchart_refrigerants_lubricants_supplemental.pdf

http://www.refron.com/InfoCenter/TechData/Honeywell_PT.pdf

those 2 online charts are ok, but any refrigerant supplier should be able to get you a real chart. NBP is -49c or so on 402a, -47 on 507, and -46 on 404a. -42 for 290 and -40 for R22. -45 for 502.

oh and you don't have to worry about your gauges, you won't be able to use them for the p/t on them, but the pressures are still there for you to check against a chart.

Gray

[Fhqwhgads6680]

Ok thanks that about does it then....looks like I'll be heading down to the refrigeration supplier in a day or two :) :toast:

[{.bLanK} GoD]

im using iceon 69L in my single stage which is a drop in gas for r502 and it runs pretty well,just a little hot, but nothing that cant be remadied :)