Why would you do this?

[navyhydronics]

Why would you ever want to mix refrigerants and if someone did how would you be able to tell, color?

[refrige-nate]

you might want to mix refrigerants if your a chemical engineer for dupont:D but other than that refrigerants should never be mixed...as for telling how there mixed, hehe color? what are your credentials? why do you ask?

[navyhydronics]

I am in the navy and i never had to experience working with multiple systems that somebody other than my division was touching, so everbody understud that the r12 plant had r12 in it. But now iam retiring from the navy and will have to deal with systems that somebody else may have serviced. Iam asking for my own general knowledge.

[icemeister]

Today with the dozens of different refrigerants available it's imperative that each system be permanently marked with the type of refrigerant it contains. Unfortunately, not everyone follows that simple rule and as such, those folks make it more difficult for the rest of us to do our job right and more costly to the customer.

When in doubt, pull it out.

I use a white paint marker on every system I work on to ID the refrigerant that's in there. If I take on a new customer and find an unmarked system I recover the unknown refrigerant, change the filter-drier, evacuate, charge and mark the system properly. I also ID the refrigerant on the filter-drier and mark the date it was changed as well. (I try to date every part I change)

[pacreefer coolhand]

Well, I think I've been where you're at before. I got out of the Navy in 1994; the refrigerants I worked with were R12, R114, and very little R502. In the civilian sector I needed to gain familiarity with R22 right away. But typically that was what we were dealing with back then R12, R22, and R502. I had an AC that ran on R500, my boss at the time told me just to put R22 in it until I got 45# suction pressure, and the put R12 in it until the suction line started sweating. I don't recommend doing that by the way.

With all the replacement blends and so called "drop ins" available, I'd say that without a refrigerant tester you have no way of knowing what you have in a system. If the system is R12, I've heard of people topping it off with whatever they have is close (MP39, MP66, Hotshot...).

They are all going to look the same color, so going by color is not going to help you determine what you have.

A good heads up would be pressures and temperatures. As long as it is doing what it is supposed to I wouldn't worry about it. If you have to add charge I would look through the old invoices (if available) and see what has been put in the system and match that. The big issue then is, can you trust the last guy that worked on it? Most here would agree that you couldn’t. If there is doubt and performance issues, pull it out and start over with virgin refrigerant.

Everybody I work with takes great care to mark the system with the refrigerant they put in it or know it to have.

[the mojo]

Today with the dozens of different refrigerants available it's imperative that each system be permanently marked with the type of refrigerant it contains. Unfortunately, not everyone follows that simple rule and as such, those folks make it more difficult for the rest of us to do our job right and more costly to the customer.

When in doubt, pull it out.

I use a white paint marker on every system I work on to ID the refrigerant that's in there. If I take on a new customer and find an unmarked system I recover the unknown refrigerant, change the filter-drier, evacuate, charge and mark the system properly. I also ID the refrigerant on the filter-drier and mark the date it was changed as well. (I try to date every part I change)

Ice Why use a white paint marker? Don't you know,use the Red one.:D

[navyhydronics]

Thanks guys, for the last 12 years i have been doing hydronics and control systems, so its been a while since i have had to even look at a refrigeration plant. Just hired on as a tech and iam studying my butt off trying to get upto speed on whats going on now days. Things will be a little different not having perm. gauges for temps and pressure set-up on the plant. Are most systems R22 or R134 ?

[icemeister]

Ice Why use a white paint marker? Don't you know,use the Red one.:D

I work on a lot of old stuff near the ocean. Red just doesn't show up good on rust.;)

[the mojo]

This is crazy..... Worked with a fellow tech many many moons ago who used to take R-500 and R-22 when he ran low on R-502 and mix them half & half. When I "tried" to explain the laws of pressures to him he would grin and say I don't know that Irishmen named Charlie Boyle.:eek:

[jasond1011]

i finally gave up replacing the oil in the compressors if called for and converting to the new ref and changing driers and all when the old r12s died , i cant tell you how many servisce companies came in behind us and topped off an r12 cgarge with 409 or mp39 or dumped 408 in with 502. no oil change , no labels, no nothing but they were a tenth the cost of my doing it right. now i only do ref for the hospitals in an enviornment i can control and only 8 to 5 unless its a walk in. just had enough of that calf licking somebody elses abortion all hours of the night.

[refrige-nate]

I am in the navy and i never had to experience working with multiple systems that somebody other than my division was touching, so everbody understud that the r12 plant had r12 in it. But now iam retiring from the navy and will have to deal with systems that somebody else may have serviced. Iam asking for my own general knowledge.

sorry man not trying to be mean just making sure your not some janitor from some apartment complex trying to fix his A/C!!!!:D yes mixing refrigerants is a no no look up Boyles law..some new refrigerants are "blended" these are replacements for older refrigerants but this is done at the factory not in the field. as for what other people do, i think my buddie icemeister said it best:
when in doubt pull it out:D

[idontgetit]

i think my buddie icemeister said it best:
when in doubt pull it out:D

This may also be his dating policy! :):D :D :D :D :D :D :D

[refrige-nate]

This may also be his dating policy! :):D :D :D :D :D :D :D

ohh trust me i was thinking it, but i kept it clean:p

[chefid]

you mix refrigerants on ultra low freezers all the time

[jonbailey19808]

thats right chefid. New scientifcs even the -20f one come with a mix of R404A and R134a in them. I learned pretty quick to put in the lower pressure refrigerant first.

[piledriver]

Why would you ever want to mix refrigerants and if someone did how would you be able to tell, color?


Simply put ,, there are good reasons to add refrigerants together. one good example would be converting a low temp r-12 system to r-22. Hmmm.. you say. well as you all now mineral oil doesnt like to attach to r-22 as readily as r-12. so in this case a small percentage of r-12 if its laying around makes a wise decision to add or mix for improved oil return to the heart of the system know as the ....... right , the compressor. oh and dont worry the pt chart will be just fine for your service work .

[refrige-nate]

you mix refrigerants on ultra low freezers all the time

this i did not know...what a noobie i am:D

[yotaman16]

this i did not know...what a noobie i am:D

Your not the only one. LOL i didnt have a clue.

[300 Win Mag]

Here too, learn somthin' everyday!:)

[Wheelbaron]

I found an old techemsche once running with r-12 and written on the side was "Added 6 oz R 409" and a date and somone's initals. It was running a little hot. I pumped the mix into my junk tank, put on a new drier, and charged with MP 39. Ran fine, and I didn't even change the cap tube, though I cut about 5" off it to compensate. Those old Techemsche compressors are the bomb.