CO2 is a GREAT substitute though. and readily available at any lowes/internet/paintball whatever.
helium works well too, but it's VERY good at finding leaks, being the smallest non explosive molecule, and the little baloon party cans work very well.

You have a vacuum pump on your car, so why not use it? That should get you to ~15"Hg vac, whereas people say 10" Hg is all that is needed to remove water (depending on temperature). I follow up w/ a hand vac pump to bring it to 20" Hg. I used to get 29" Hg fairly easy w/ my Mighty-Mite pump, but the HF version seems to take more work. I made a little charging setup - cut a fill hose in half, added a T w/ a valve so I can change the vaccum source and isolate it. I have the can on the hose far side as a dead-end, and don't pierce it until the vaccum job. I leave under vacuum ~4 hrs to be sure. No vac leaks doesn't assure you won't have leaks under pressure, but "better than nothing" and I have never had leak. Actually, I did have a leaking Schraeder valve on my 96 Voyager low-side port recently, right after filling (drats), but I pulled the stem out w/ needle nose pliers and stopped it. People say some AC gage sets can bend the stems. If >20 yrs old, I would change the filter/drier (cheap) because I read they have bags of desicant inside that can come apart and send stuff thru your system.

Also check the Duracool site. I have used them for decades. I checked Envirosafe and was confused by their 2 products. Why can't you apply vacuum first w/ their cheaper refrigerant? Makes me wonder if it has ethanol or such. Their "industrial" costs about the same as Duracool after shipping, so I stuck w/ Duracool. I also have an MS in ME and agree that the Envirosafe tech comments reported above make no sense to an engineer. BTW, if changing compressors, look at PAO 68 oil (Duracool's "Oil Freeze"). It doesn't absorb moisture like PAG and works w/ all refrigerants.

I question post #16 that CO2 or Helium would work as a refrigerant in our cars. The condenser and evaporator rely on the fluid changing phase at particular temperatures. You won't condense Helium period, and unlikely CO2 would match what we need. You could get cooling w/o condensing (say just air), but it would be very minor. There is much more energy transfer at the phase change points.

Hmm....I had the understanding that helium or CO2 was used for pressure testing, not as a refrigerant.

I think using the car's vacuum pump is an interesting idea. I might have to explore that option.

vstech was talking about using CO2 or Helium to find leaks, not use as refridgerant. I myself, have been using argon gas and a shot of R22 (because I have them in tanks already) with an electronic sniffer to detect leaks.

Back to my original question, from some people's responses, it would seem I could be lazy with Enviro-Safe. Use the same one year old drier, deep vacuum for an hour and charge with ES Industrial r12a. Moisture and a little contaminants not an issue with ES.


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All does make sense if you have pressurized gas for testing.

Wondering what you end up doing and how it worked out with the Enviro Safe?

My 85 is on R134a currently and I have been topping it up with a can or 2 every summer. It cools acceptably but I wouldn't mind if it cools better.

I have a kit from Enviro Safe (3x 6 oz cans of ES12a refrigerant, 1 can of dye charge, 1 can of stop leak). I also have a 90% full 30 lb jug of R12. I really want to get rid of the 134a and try the Enviro Safe to see how it performs as that is a lot less work than going back to R12, which will require a complete flush, pressure test, evacuate and charge.

This is really a sad thread.... so many people with so little knowledge of the physics involved in an AC system...and willing to share that with others....
Vstech and I have spent years trying to get rid of many of these truly bad ideas...it looks like it is hopeless..

Just one example... Vstech and I have been suggesting the use of nitrogen and a four oz charge of a refrigerant which is ' sniffable' ...because using pressure tests the joints under the same situation the working pressure is.. the EPA allows that four oz charge to be released into the atmosphere legally...on the theory that sealing up the system properly is better than losing can after can of refrigerant due to leaks... this stuff is all in the thread in my signature on AC...
People who are going to use dye to find leaks.... tell me how that will help you find a leak in your evaporator ? My wagon had a leak in the evaporator.. and just sticking the sensor into the center vent caused all sorts of beeping.... a dye will do you no good... and you may even cause a blockage...

https://www.justice.gov/opa/pr/enviro-safe-refrigerants-agrees-halt-sales-unapproved-flammable-hydrocarbon-refrigerants

I apologize for not making an update. I never made it to EnviroSafe. I just installed a new drier and used the r12 I had in my 30lbs jug.

But if you ask me about my opinion on having r134 in a w123? Get it out of there and use EnviroSafe. I am not a big fan of the higher pressure related to using r134. EnviroSafe is much lower pressure which translates to less drag. If not R12, then ER12a would be perfect to use with a R4 compressor.


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When I started this thread, I was just waiting... Just waiting... to hear from you.... What took you soooo long! lol



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Why , after doing the right thing, would you suggest the wrong thing to other people?

Some people don't want to screw with R12. Hydrocarbons are a fine refrigerant, and legal to drop into a 134a car in most states.

I don't know why this is such a hot-button issue? How many things are done by the book on 20+ year old cars worth $500-$5000? If it works, enjoy the cold air. If not, then explore other options!

:)

The wrong thing? I am not against es12a. But if folks understand that ES12A is a flammable substance and do their own research, I think it would be a good alternative.

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It is clear that you people do not read the url's posted as references...
and do not do your homework with regard to the physics of the situation....

I read and followed the instructions at Enviro Safe's site. I did my home work.

With my manifold gauge, I slowly vented what's left of the R134a into a bottle of water till there are no more bubbles, i.e. system at atmospheric pressure. I charged all 3x 6 oz cans of ES12a as a liquid into the low side. My 85 takes 2.9 lbs of R12, that calculates to a little over 2.5 x 6 oz cans of ES12a but with the venting to purge the lines, I figure 3 cans is about right.

What I end up with is 43 psi low side and 150 psi high side at idle and 40 F chill out the vent cruising on the highway. I did inject some dye last summer into the 134a to look for leaks but did not find any. Maybe the 134a is slowly leaking out the non barrier hose? I am tired of having to buy 2 cans of 134a every cooling season to top it up. I am hoping the lower pressure and larger molecules of the ES12s will stay in the system longer. Time will tell.

Sorry it was a sad day for you LMG but it's a super happy day for me. Here are some pics to cheer you up.
http://i31.photobucket.com/albums/c3...530_144304.jpg

http://i31.photobucket.com/albums/c3...530_135837.jpg