according to the website selling this product, it is indeed a hydrocarbon; however, is this particular compound flammable? Any chemists or fine-particle physicists out there?

http://glacier-gold-refrigerants.com/Glacier-GOLD-12a.htm

I'm about to recharge my 300CD's A/C system. It still has a little bit of R12 in the system and still blows somewhat cold when the weather is mild out. However when it's warm... it just doesn't cool as much.

I was quite set in recharging it with FR-12.. which I think is that Freeze 12...
Now I'll think twice about it...

*nevermind, I just found this site..
http://www.refimax.com/products/fr12.htm#
and apparently Freeze 12 is different to FR-12...*

sigh never thought it was this complicated.

Why is it that from reading this thread, it seems that R134a isn't as cool as R12?

__________________
2008 BMW 335i Coupe

I posted early on in this thread about Freeze-12 being 80% R134A and 20% ???

Here's the breakdown:

80% R134A
20% R142B

You also need a special tap(mfg supplied of course) that fits the can. An R-12 tap won't fit the Freeze-12 can.

I think everyone will have to come to their own conclusions. I know people who've recharged empty R-12 systems with R-134A and it worked great and not just for a day or two.

It all depends on the individual situation. You need a 609 certification to buy Freeze-12. The fact that's it's been around for as long as it has would imply it's legal to use. What the mfg. is somewhat emphatic about is the use of proper fittings and the relabeling that's supposed to take place. Whether or not anyone does this is another story.

Both Freeze 12 and FR12 appear on the list of EPA approved substitutes (note that approved means as far as environmental factors - not compressor longevity or chill factor.)

http://www.epa.gov/docs/ozone/title6/snap/lists/mvacs.html

The FR12 is listed as R416A HCFC blend, (HydroChloroFluoroCarbon), Freeze 12 is 80% R134A, and HFC (no Chlorine), and 20% R142b, an HCFC.

http://www.epa.gov/docs/ozone/title6/snap/lists/refblend.html


Freeze 12 distributors list a number of claims. One site states that it is a 'drop in' replacement for r12 - a clear violation of EPA law which states there are NO drop ins, and that separate equipment, labels, evacuation pumps, and fittings are required by federal law for each refrigerant/blend, and that they can't be mixed during recharge/conversion.

More realistic commercial info is at this site:

http://www.technicalchemical.com/tip-5.htm

which also notes that new compressors are not guaranteed for Freeze12, but are for r134a. Most of the conversion info you will need can be found at the EPA sites. Manufacturers/distributors claims should be treated like the claims of Cigarette companies regarding their products not causing cancer!

BTW, my 87 was legally coverted to r134a 2 years ago, and I can't tell any difference in how cold it gets, just a slight increase in time getting to the cold temp. It is still capable of making me colder than I want to be, even during a SoCal August heat wave. My temp wheel is at the same location as before the conversion.

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E

Hydrocarbon based refrigerants (Duracool, HC-12a, Enviro-Safe, etc.) are some of the most environmentally safe, but completely misunderstood, alternative refrigerants available on the market.

It is true that hydrocarbons are "flammable" but they are completely safe to use as directed in appropriately designed equipment as an alternative to freon. There is an unfounded fear of hydrocarbons in the industry due to the moniker "flammable" but, think about it, you use flammable products everyday. When you get in your car or truck, you are using a highly flammable compound to power your vehicle but you never give it a thought because you are using the flammable in a properly designed, appropriate piece of equipment.

Hydrocarbons are being embraced worldwide because they are non-ozone depleting and almost totally non-global warming. Additionally, since hydrocarbons are made entirely from natural, organic products they are completely non-toxic and safe to the installer and material handler. In addition to safety and environmental issues, hydrocarbons have also been proven to add life and performance to air-conditioning and refrigeration equipment. Since hydrocarbons are more efficient than CFC and HCFC substances energy savings of up to 35% have been recorded in systems using hydrocarbons.

Hydrocarbons are being hailed by many as the coolants of the future. As the older CFC refrigerants (freon) are being eliminated, many governments are now turning their attention to the restriction and eventual phase out of HCFCs such as 134a. HCFCs have been shown to be Global Warming substances although not as dangerous or destructive as CFCs.

__________________
I got too many cars!! Insurance eats me alive. Dave

78 Corvette Stingray - 3k
82 242 Turbo Volvo - Manual - 270k
86 300e 5 speed manual - 210k
87 420sel - 240k
89 560sl - 78k
91 420sel - 205k
91 560sel - 85k
94 GMC Suburban - 90k
97 Harley Davidson Heritage Softail - 25k
00 GMC Silverado 1 ton 30k

Actually, R134a is an HFC, not an HCFC, (no chlorine or bromine)and per the EPA has zero ozone depletion potential:

"Hydrofluorocarbon (HFC): a compound consisting of hydrogen, fluorine, and carbon
The HFCs are a class of replacements for CFCs. Because they do not contain chlorine or bromine, they do not deplete the ozone layer. All HFCs have an ozone depletion potential of 0. Some HFCs have high GWPs. HFCs are numbered according to a standard scheme. The National Oceanic and Atmospheric Administration provides more detailed information about HFCs on their web site."

Also, Methane gas, a hydrocarbon, is a demonstrated contributer to global warming. Again per the EPA

http://www.epa.gov/globalwarming/glossary.html

"Methane (CH4)
A hydrocarbon that is a greenhouse gas with a global warming potential most recently estimated at 21. (about 21 times the warming potential of carbon dioxide, but less than the warming potential of HFCs or HCFCs) Methane is produced through anaerobic (without oxygen) decomposition of waste in landfills, animal digestion, decomposition of animal wastes, production and distribution of natural gas and petroleum, coal production, and incomplete fossil fuel combustion. The atmospheric concentration of methane as been shown to be increasing at a rate of about 0.6 percent per year and the concentration of about 1.7 per million by volume (ppmv) is more than twice its pre-industrial value."

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E

So, if I wanna recharge my AC (which is currently filled w/ a lil bit of R12), I have to evacuate the system first right? (Before I fill it with FR-12).

I mean they don't mix, do they?

HEY GUYS, THIS WAS A GREAT THREAD, THANKS TO ALL FOR GOING TO THE TROUBLE TO POST SUCH GOOD INFORMATION....

My question is:

If , here in Texas , I needed a little more cooling capacity....( I have heard people say that it was only in stop and go traffic in the heat that they felt a difference in the 134 compared to the 12)....lets say I want to convert to the 134 but try to minimize that difference or eliminate it entirely....(because in stop and go traffic is when I most need my ac... !
Does anyone know if some upgrade like using or making a larger condenser would be addressing the problem in the right direction ? Could two reciever/dryers be used hooked up in parrellel to increase the amount of 134... assuming that it has less ability per unit of quantity... and I would like to increase the volume... ? How about a list of the first/most logical itemS to upgrade (and what that means in that case ) In other words.. am I barking up the wrong end of the tree and need a bigger evaporator, for instance... Thanks, Greg

I can make one.... so don't get hung up on the fact that bigger units are not available for my 1981 wagon...

I emailed the company with many of the concerns expressed in this thread; here is their response, which includes the acknowledgement that it contains propane:


"It is not corrosive nor does it turn acidic in the presence of moisture. The autoignition temp is much, much higher than that of 134a which goes in every newer car. The autoignition temp is 1,585F. At that temp, the tires would liquefy, the seats would catch fire, the metal would start to melt, and the
driver himself/herself would burst into flame as well. All of that would happen long before the refrigerant started top burn. In that scenario of well over 1000F, I would worry about the gas tank wouldn't you.

Yes there is propane in it. That is one reason it is so darn effient. Hydrocarbon refrigerants were first envisioned by Albert Einstein and he tried to patent three different types all involving hydrocarbons.

134a on the other hand will kill you if you inhale it at more than 4% concentration. Additionally, Coke, Fosters Brewing and Unilever (worlds largest icecream maker) have all made announcements regarding their intentions to use hydrocarbons instead of 134a or Freon. In Germany 100% of all new refrigerators use pure propane as the refrigerant. There has never been a hydrocarbon refrigerant fire ever, in over 20 million user years.

Randy
AutoRefrigerants.com"

Yes, there is an improvement that can be made, and its called a parallel flow condenser. They are sold very inexpensively at this site (although some custom work will be necessary to mount it and hook up the hoses):

http://www.ackits.com/content/cddata/mfcond.htm

Your question is asked quite frequently at www.aircondition.com, a technical webpage for automotive a/c, and this is the common answer. You also need to make sure your electric fan works properly. I know most new cars are wired to turn on the electric fans when the a/c is on. Are Mercedes the same way? I am currently rebuilding my a/c, so I don't know yet how the electric fan works, but if it doesn't run at all times when the a/c is on I think I will wire it so that it does.

Greg
'84 300D

Greg, thanks much for the url, Greg

If you are looking for effeciency at high thermal load with the
stock condenser, you may want to consider high fan speed
vs. the normal low for condenser air flow cooling.
I have toyed with the idea of low speed resistor jumping .
There are also several other ways this could be accomplished without spending big $$$.
High side condenser air flow improvement is a good place to start......

Yet another touchy subject. If you use any of these aftermarket freons besides real r12 or real r134a then you might as well mix in some water and cryo seal in there too , cause all you are doing is making a very strong system weak as for components. We went to a school where they had a 116 chasis car with a leaking evaporator filled with freeze 12 , had 2 candles sitting on the dash blower on low speed and 42 minutes later boom all windows gone and car on fire. These companies are not going to back up their product if it ruins your system. Go with what the vehicle manufacturers recommend on this system. Talk to any of the professional technicians on this board , they will tell you dont use this junk. Remember these guys experience this every day for 8-10 hours . We know what works and doesnt work. We have been there and fought it. Free advice is hard to come by, I wish they had a doctors board that would give me free advice it would save me $$$$$$$ in health insurance. Good luck and take it in.

__________________
euro 287
Mercedes Technician 7 Years (retired to Hyundai)
2000 Dodge Durango
98 Mazda truck

Euro 287, just to clarify as your info as its quite alarming, that the product was hydrocarbon based and that a similar test conducted with r134 did not explode or if it did how sooner or later.

so, i imagine it this way: driving down the highway one hot summer day, ac on, windows up, someone lights a smoke and kaboom!

Yes, as stated originally, different refrigerants are OK'd by EPA for different purposes. Even hazardous ammonia is OK for a stationary food refrigeration plant. (Not many of these collide at 65 mph, so the hazards are different.)

Also as stated earlier, the manufacturer is not the preferred source of info, and may misdirect you to different info. For example, Autoignition temperature, the temp where a material will self ignite WITHOUT THE PRESENCE OF AN EXTERNAL IGNITION SOURCE (such as underhood wiring, coils, etc) is a different consideration than flash point or upper and lower explosive limits. Consulting the Manufacturers Material Safety Data Sheets provides REAL data.

For example, the autoignition temp for propane is 871 F, but the propane flash point is -156F, and the LEL/UEL (lower and upper explosive concentration levels) are 2.1 to 9.5%. Gasoline has an autoignition temp of 495F, a flash point of -50 (less hazardous than the propane), and a more narrow range of explosive levels 1.4-7.6% LEL/UEL. R134a has no flammability, autoignition temp, or flash point. It is NOT flammable, whereas propane and gasoline are both listed as Highly Flammable. The "much higher autoignition temp than r134a" exists because the non-flammable r134a quenches the autoignition temp of the propane, and ANY temperature is 'much higher' than no temperature.

While r134a can decompose at extremely high temperatures to create acids, and has lethal asphyxiation capabilities and medical side effects at very high concentraions, Propane is an anasthetic gas at moderately high concentrations, and is also an asphyxiant at high concentrations. It will kill you just as dead as the 134a.

The NFPA lists r134a as a 2 out of 4 (4 being worst) for health effects, 0 for flammability, 0 for reactivity. Propane is listed as a 1/4/0 - less of a health effect, maximum flammability, no reactivity.

Since Freeze 12 is apparently a mixture of 80% r134a and 20% propane, I fail to see any health advantage (in fact, there is now a sum of the health hazards). Also, a flammable component has been added to the 'mix'.

This is not a pitch for people to use r134a, or a defense of the EPA as the ultimate authority for everything, or a claim that cars are going to burst into flame from using Freeze 12. It sounds as if a proper legal conversion may be a good choice for a refrigerant, and it is on the EPA authorized list. The possible extra cooling from adding 20% propane to r134 may offset the minimal increase in flammable material accident potential. The issues of proper conversion, compressor warantee, proper labelling, oil compatibility, etc. are also worth considering.

To deny, minimize, or obfuscate that there is a hazard, even a very small one, is irresponsible. To claim 'Drop In' status is illegal. The only manufacturer document that is certified to not be an advertising pitch or redirect of your question is a Material Safety Data Sheet. If you don't have the experience to use the MSDS, then go with the EPA determination over a manufacturers advertising, FAQs, or 'facts' quoted out of context or for systems not remotely similar in application to your proposed use. Then research the issues EPA doesn't cover, such as compressor life span.

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E