Mixing refrigerants? (let the flames begin)

[Executioner]

Ok guys and gals... I KNOW it ain't right or what's taught or what they say ain't comtatible (so they say) HOWEVER!

I have come across units that have been marked by passed tech's "R-12/134A/409/hotshot.mix. And are working fine after I repaired a small leak and partially recharged with what I had on hand (134a).

I've also used R22 instead of 404a to get a WI freezer running after fixing a leak, havn't had to go back in 6 months and used 3lbs on a 8lb system.

The equipment,refrigerant,oil and other manufacturers adamantly proclaim that they WON'T mix but they will.

Now before you get your panties in a bunch! I don't do this all the time as a general practice, but only in a pinch. If the system pulls down to temp. then I leave it at that.


you can get as technical as you want but, R12,134a,409,hotshot,and a few others ALL have REALY close head pressure.. and the bottom line is protecting the compressor. R 502,404a,r22...ect are the same.


NO they are not intercomtatible with P.O.E. oil and Mineral oil. I know this but if it's a mix then as long as the majority is oil compatible it will work. Reduce performance and life???? maybe.


My proof I recently came across a 1 door upright freezer that was to be scrapped,marked 404a, The comp. worked so I fixed the evap. leaks and weighed in the 16 oz charge of as equal parts I could of 134a,404a,22,409a.

and also some recovered witches brew

Well it reached -10 F in 45 min. from 80 F.

Hmm?

Now let the beatings begin. (no I didn't make this up to provoke you guys...)

[jimj]

this should be good. LOL

[Executioner]

The 1 door upright at the end of the post is my guiene pig (spelling?)

(not a customers! In my driveway enjoying the 90+ F weather.

[VTP99]

I love your thinking outside the box. You know this is really going to upset some people right ? Maybe you could come up with your own flavor oh that's right you already have. I do know of a W/I cooler that was R409 and switched to R134a with no oil change. Dang thing has been running like a Swiss watch for the past 5 years.

[craig1]

and the bottom line is protecting the compressor. R 502,404a,r22...ect are the same.

502 and 404a will get along fine as long as you have enough 502 to transport the oil. 22 doesn't belong there. at least not too much of it. runs high head pressure, compression ratio, and discharge temps in low temp applications. Its a quick way to a cooked compressor on a system not designed for it.

[jpsmith1cm]

I know a lot of guys who will mix the R-12 variant refrigerants (401a, hotshot, etc) and claim no problems with operation.

I have never knowingly mixed refrigerants and never will.

When working on larger equipment (1000+ pound charges) throwing in 200# of R-22 in an R-404a rack may work, but it may also have consequences that I don't want to consider, such as me losing my job when my company has to pay for the recovery, replacement and disposal of a half ton of junk gas that I created.

[adam_s05]

i've topped off a 404 WIF with 22 once in a pinch, but i only did cause i was working in a fly in only location and didn't have time to wait for 404. this was over six months ago and the unit is still working great.

[VTP99]

If you do decide to mix refrigerants there is one tool you will not need. Do you know which one ?

[hvacker]

Propane is a good emergency substitute for R12. Just don't have a leak.
I know if you substitute the old 70's R500 with R22 it will cost you.

[craig1]

I know if you substitute the old 70's R500 with R22 it will cost you.

I have a customer (church) that had an r-500 system that i topped up every year with 5 lbs r-22. worked great. Untill the compressor fell out and ripped off the suction line. Then they got a new r-22 condenser and TXV

[hvacker]

I have a customer (church) that had an r-500 system that i topped up every year with 5 lbs r-22. worked great. Untill the compressor fell out and ripped off the suction line. Then they got a new r-22 condenser and TXV

A shop in Illinois serviced a, I think, 10 ton Carrier heat pump. After three compressor failures someone read the data plate. It was a R500 machine that was serviced with R22. Some were sworn to secrecy.
There are large operating pressure differences between the two. R-12 is a lot closer to R500 than R22.
My guess is the compressor stroke is different as the cfm should be different for the two.

[76olds]

If you do decide to mix refrigerants there is one tool you will not need. Do you know which one ?

P.T. chart? As far as R500 goes, it is really close to R12 but the head pressure is higher(I think, it's been a rough 2 months, at least i think it's been 2 months, I'm really burnt out right now). Couldn't you pull out the 500, and recharge with R409a and it would be fine. We actually have R500, so if I had something that old, I could put the right juice in it.(The R500 is buried along with the R11).

[Retread]

I have always wondered about that. Boss wanted me to carry hotshot but not 134 so I was alway recovering the charge and recharging with hotshot. I finally started carrying 134. Life is now easier.

[VTP99]

P.T. chart?

P.T. chart. My thought exactly.

[sprintmj19]

Great post in an open forum....I can see it now...

What kinda FreeZone ya got wit ya???

R what? Aw, shoot, it don't make no differnce, they's all the same!!!

Go ahead and charge that bad boy right up!!!

Them thar Profeshunals on that there googly moogly forum say theys' does it all-a-time.

Git-R-Done!!!!

[The Penguin]

I was out of town 5 hr drive to go get 12 - I should have had enough but I didn't - farmers dog tucker cooler ( or freezer ) I don't remember - repaired leak woulda caught hell if I had to go get 12 - I finished it off with 502 a bout a 1lb of 502 to 12 lbs 12

never heard a thing ( I figured 502 was partly 12 anyways )

[hankmoody]

I'm a little confused...if you put r-22 in a r-404a system, whether the capacity be 8 lbs (and you add 3lbs), 200 lbs (and you add 60 lbs), or 1000 lbs (and you add 100 lbs), wouldn't you have to adjust the txv's or anything? Since the boiling points, etc. of both refrigerants ARE slightly different?

[jpsmith1cm]

I'm a little confused...if you put r-22 in a r-404a system, whether the capacity be 8 lbs (and you add 3lbs), 200 lbs (and you add 60 lbs), or 1000 lbs (and you add 100 lbs), wouldn't you have to adjust the txv's or anything? Since the boiling points, etc. of both refrigerants ARE slightly different?

Let's do it this way.


DON'T MIX GAS!

[hankmoody]

Let's do it this way.


DON'T MIX GAS!

oh, i do it that way. i'm just confused how he's saying it'd work when they have different boiling points and such

[2sac]

Why open yourself to potential problems?