In theory yes, but it's got to have something to do with the possibility that propane is a component of the mixture. I'll try to get the MSDS sheets and post them. If ES-12 was indeed safe, the EPA would be promoting the heck out of it. Commercial, residential and automotive applications would be changing everywhere with similar refrigerants available, due to the non-ozone depleting factors as well as no recovery or recycling of refrigerants.

Can I ask a really DUMB question Chris?

Uhmmm... Is this stuff legal to put in our cars? Or more importantly, is it legal to sell and purchase for the use of in a car? Or is this hopefully one that is currently slipping by regulation....

Jeez Jim, you guys have all the answers:o

I guess the above link dispells any questions of leagaity!!!

Buy it while you can, but use it at your own risk.........

Damn... forgot to spell check! LEGALITY?

Thanks for the articles Jim. This thread has really gone a long way in a short time.

Can I ask a really dumb question now...what are the temperature readings at the vents for those of you that have done the R134a retrofit?

I knew I really didn't want A/C in the 911 anyway. :)

After a fresh charge, I will usually see a 30 degree difference at the floor vent vs. outside air temp when car is moving on the freeway.... OK, I guess, as long as it doesn't get above 95 outside.... I used to see about a 40 degree difference with the wonderful R-12... If I can score some of this new stuff, and it really works in my system, I might just just buy a couple of cases of it, and store it next to the rest of my militia gear...

This link takes you to a MSDS for Envirosafe refigerant. The composition, as listed on the MSDS is 0-60% C3H8 (propane) and 0-60% C5H10 (probably cyclopentane). Both are flammable, and propane appears to be a major component. Cyclopentane is slightly less flammable than propane, and linear pentane derivatives that fit that formula will be just as bad as propane.

http://befreetech.com/esmsds.htm



The MSDS for cyclopentane is below.

http://ptcl.chem.ox.ac.uk/MSDS/CY/cyclopentane.html


Per the MSDS, cyclopentane is "Highly flammable. Note low flash point and wide explosion limits. Incompatible with strong oxidizing agents. Floats on water so water is of limited value in putting out fires involving this material."


If you choose to use it your car, just be aware of, and take responsibility for, the risks. After all, it IS still a free country.

remember 134a is 1,1,1 tetrafluoroethane

I'm not sure this makes me feel any better either.

The fluorines make it a lot less flammable than propane or another hydrocarbon. For instance, chloroform, CCl4, was used in pump style fire extinguishers up until the 30's or '40's.

Another very good refrigerant is ammonia. Of course, if you could get past the severe toxicity, you sure would know if you had a leak in your system.

Another quote;
"The autoignition temp of 134a is 368F !!! Not only is that do-able under the hood, but if you breathe it at only 4000 parts per million, you die".

In the PDF about the professor's experiment, with the coolant he used, I think they mentioned that the vents were approximately 2000 degrees cooler than the professor's head...

perhaps the flame aided in causing a chain reaction (autoigition) by the new higher temperature inside the Professor's chamber of horrors?

"but if you breathe it at only 4000 parts per million, you die".

Sigh!

The below is from:

http://www.trane.com/commercial/issues/environmental/cfc6.asp#toc

R-134a toxicology.[10] R-134a also has very low acute inhalation toxicity. The lowest concentration that causes mortality in rats, the 4-hour Approximate Lethal Concentration (ALC), exceeds 500,000 ppm. The cardiac sensitization response level for R-134a is approximately 75,000 ppm. Anesthetic-like effects are observed at concentrations greater than 200,000 ppm, or 20%.

Long-term exposures with very high concentrations (50,000 ppm) caused an increased incidence of benign tumors in the testis of rats. Again, none of the observed tumors were life threatening, and all occurred near the end of the study. The evidence from all tests in cultured cells or organisms, as well as in laboratory animals, indicates that R-134a is not genotoxic and that the increased incidence in benign tumors is not due to an effect on genetic material.

The test findings indicate that R-134a has very low acute and subchronic inhalation toxicity, is not a developmental toxicant, and is not genotoxic.[10] Most refrigerant manufacturers recommend that TWA occupational exposures not exceed 1,000 ppm; this also is the level recommended by the American Industrial Hygiene Association, Workplace Environmental Exposure Limit (WEEL) Committee.[11] Again, exposures still should be kept to the practicable minimum. (A WEEL guide has not been published for R- 123 at this time.)

It is important to note that the tumors attributable to the R- 123 and R-134a exposures were not cancerous. The findings reflect an increase in tumor incidence compared to rats in the experimental control group, those not exposed to the refrigerants. Some tumors also were observed in this control group, but not as many.

Also, the recommended occupational exposure limit for each refrigerant is below the level at which toxic effects were observed in laboratory animals. The use of rats, dogs and other animals is based on accepted scientific procedures and sensitivities to specific concerns by species. The lower exposure limit affords both a margin of safety and a conservative reflection of potential differences, between responses in individual humans and between humans and test animals.

Other refrigerants. Information on the toxicity of other refrigerants is available from chemical manufacturers, published literature ,and chemical and safety databases. The toxicology findings for other refrigerants covered by PAFT are also available.[10]

R-123 and R-134a were summarized here as the newest of the widely used refrigerants for chillers. Other chiller refrigerants are addressed in less detail below, and a survey of toxicity data is underway, by the author, on alternative refrigerants for additional applications.[12]

Patrick,

At home I can lounge by the pool with a margarita in hand legally. Same cannot be said about the car! :)

JoeA

If you new that your system was leaking, It would be important to know if it was leaking "into" the system, and mixing with air entering the cabin... If it was leaking out of the closed system, obviously it would likely dissapate before causing any human harm? How much refrigerant actually ever bleeds into the closed system exposing possible harm to those in the car?

Yikes... Where is this thread going??

Without drawing my comments out for too long, let me say I have researched this topic before.
I found a link that was especially helpful for me. Of course, it is on the net, so take it for what its worth, but it certainly seems to clearly explain most common questions, facts, and myths about refrigerants, retro-fits, risks, and what should be done when switching between the various refrigerants. I read the articles from the beginning down to the following line and was satisfied. (about 2 pages)

"Discussion and alternative automotive refrigerants"

Hope this helps somebody
-Matt

oooops!

http://www.allpar.com/eek/ac.html

Yeah Joe, but what's the temperature of your pool?

Jim is correct. It is important to know that R-134a is known in drug delivery circles as HFA (hydroxyfluoroalkane) 134a and is the only current approvable inhalation drug delivery propellant in North America and Europe. It is used to deliver millions of doses of asthma and other drugs to people all over the world in MDI's (metered dose inhalers).

The HFA molecule is also about twice as large as an R-12 molecule, but the hoses in older cars will allow 134a to diffuse through the hose material, neccesitating the use of barrier hoses for conversions on older cars.

I worked in a cheese factory as a teenager and that's what they used in their refrigeration system. Even the smallest leak was detectable. I believe it was quite old. (1950's)

Re: Info for R12 users
 

When I purchased my car I had the wrench check the AC. He couldn't detect any leaks using UV dye so he figured the evaporator is shot. Anyhoo, as I have a Targa I decided to forget about AC. If this refrigerant does the trick perhaps I'll consider having the AC fixed.

AC is nice when it's muggy / rainy out. (Targa roof on) .... or just blowing on your feet with roof off!

Kato

Anhydrous ammonia isn't specifically toxic unless you get a huge overexposure. The hasmat on the stuff is much scarier then the real life reality is. The OSHA 8 hour continous exposure limit is 50 parts per million. The short term exposure limit is way higher. I personally have gone into a room to close a bottle that had leaked about 80 pounds of ammonia in about 2 minutes. (I did hold my breath.)

Now if you spray it on yourself you will get corrosion burns on the frostbitten areas.

I have never met anyone who isn't acclimated to ammonia that could stay in a room with over 5 ppm and their eyes would be running at that level.

I still think it would be way too much work to put it into a car unless you could hook it into a car alarm that would discharge a small quantity of ammonia. The attempt to steal the car would quickly stop! Hell, they wouldn't be able to get close to the car. :D

Great idea!... But first, we'd have to kill all the lawyers:D

Chris,
I am still searching the site you reference in this statement. Where can I purchase some Enviro-Safe?
Thanks,
Paul

The Coooooool web site! :D

http://autorefrigerants.com/

Thanks Patrick!

Unless you have a seiko seiki compressor, the original nippondenso compressor that came with your PORSCHE is a wobble plate compressor.

Joe from the Jag group? what happen to Joe from the PORSCHEGroup?

I still have the ND compressor on the car, sorry am not an expert on the various types!

Hey, I am also "Joe from the Aeronca group," "Joe from the BMW group" as well as "Joe from the Austin Healey group" so am well spread around. Terry, the guy I mentioned is a Jag owner and he would not know me as a 911 owner.

Chris, the pool was about 87 degrees today. Lounged there while sipping a Miller and catching some rays. Totally forgot about cars, bikes etc for at least 30 minutes!

Joe A

Nine9six., I'm glad Pat replied, I've been out doing what Joe described, even though my pool is 91 after running the aerator for the last few days. Here's to life!!

A little more info on R12 replacements:

http://www.epa.gov/Ozone/snap/refrigerants/hc12alng.html

xxxx

Just a bump to see if anyone has purchased the Enviro-Safe refrigerant and has some results that they wish to share?

received my order of ES-12a industrial strength the other day. I'm still pondering the purchase of a procooler R/D. I'm probably going to bite the bullet and buy one, then do the change over... As soon as I do, I will post my results!

I just received a case of the industrial grade ES12a. I'll be taking it to a friends AC shop on Friday for installation. We'll evacuate all the R12 and fill the entire system with the new stuff. Being a little slow, can anyone answer this question? My 77 911S AC system has a capacity of 47.6oz of R12, right? If this is correct, woyuld I then charge the system with 16 oz og the ES-12a? If what I'm reading, the equivalency ratio is 3 R12 = 1 ES-12a.

Any thoughts will be appreciated. I'll post results of the installation soon.

Thanks!

Jay
1977 911S
37,000 original miles

Jay, I'm installing the same in my car next Wednesday... Your estimates are correct, as far as I can tell... Check out the VERY informative link below, and hit the link for Enviro-Safe Refrigerants. They say that each 6 oz.can of it is equivalent to_18 oz./Freon or_16 oz./134a

www.autorefrigerants.com

Please post your results!!

Good luck!

Pat

Update for my A/C...
I changed out the factory r/d to a ProCooler unit. Also switched to the Industrial Grade of ES12-a. The R/D change out was nothing short of a complete PITA!!!!!!! But boy were the results worth it!!

I'm seeing 35 degree temps at the center vent with outside temp at 84 degrees today. That would be driving in the city at 35 mph. More interesting than that, when idling at a stop light for 2 minutes, the vent temp didn't raise even 1 degree! Before, I would typically see an immediate 10 degree temp increase within the first minute...

Before the change, I would typically see only 55 degrees at the vent. Unfortunately, I didn't try the ES12a in the system prior to changing out the R/D...... This r/d unit looks to be almost 4 times the size of the OEM unit... I guess the real test will be when I see 100 degree outside temps, which are forecasted here for the next several days...

Patrick,

I changed to the ES12a industrial grade last Thursday. I live in Charleston, SC and the day I went to my friends shop to do the switch, the temperature outside was 93 and the R12 in the system was giving me an outlet temperature of about 60. After the switch, outside temp was 95 and outlet temp was 41! Great stuff!

Both temps at the center outlet were taken while cruising at about 50mph.

Jay
1977 911S
37,000 original mile

Awesome Jay!

Let's see how long it holds up.... I'm curious to see how the system will hold the charge, as I still have the original barrier hoses... But at $6 a can... Who friggin' cares!!!!!!

What has surprised me also, is how the vent temp won't fluctuate at idle in traffic, as we all know was a huge bummer with the old system... Is that a function of the ProCooler? Not sure... I'm curious to know how your system performs at idle, and in stop & go traffic... As I just did my change yesterday, I'll keep you posted as to how mine performs as well!!

Patrick,

I haven't done much stop and go with it but I'll watch and let you know.

When I bought the stuff, I hadn't paid much attention to the amount needed so I bought 24 cans! I'm 60 years old now and just hope I have enough to use it all up.

Jay