New R-134 R-12 Freon replacement??
 

Just talked to a company selling a product called Glacier Gold Refrigerant. I'm a little leary - sounds too good to be true. They say it is compatible with R-12 and R-134 so can be used to top off both systems. It can replace both refrigerants using 6 oz of their's to replace 16 oz. of R134 or 18 oz of R-12. They say it is compatible with ALL oils. They claim it is colder than R-12 and the compressor works 30-40% less as their product is easier to compress - resulting in more gas mileage and longer life for compressors. It's apparently hygroscopic so small amounts of moisture in the system will be absorbed so it won't damage compressors or components - no need to draw a deep vacuum - 5 inches as opposed to 29 (charging into a deep vacuum will result in an overcharge). Best of all it is only $10 a 6 oz can or is available in 30 lb cylinders. It is totally enviromentally friendly and requires no license in USA or Canada to use. Their website (not very good) is http://glacier-gold-refrigerants.com/ with a link to their parent company.
HAVE I DIED AND GONE TO A/C HEAVEN - OR IS THIS A SCAM???
They say they have been selling it for over 3 years now. I would appreciate some input. If true it sounds like a godsend for DIY.
Thanks
Maurice:confused: :confused:

Maurice:

Personally, I'd be leary.

I purchased some "Freeze 12" about a yr. ago thinking that I was purchasing an R-12 replacement. Later on I stumbled across some info about it and learned it was 80% R-134 and 20% R-something-or-another...forget what it was.

You can buy R-134 for half of what these guys want for this Glacier product. It would be interesting to know what the content of it was before purchasing?

how did the freeze 12 work??

I didn't use it in my R-12 system because it was 80% R-134. Somehow it made no sense to put what amounted to R-134 refrigerant in an R-12 system.

I'll likely use it down the road on one of my daily drivers when the compressor goes out on it.
I think for now, I'll continue to use R-12 in my Benz. I have a 609 certification, so I can buy it.
I've found that garages charges 3 to 4 times more for R-12 than they pay for it. That's why I have a 609 certification.

Based on the very light weight of this stuff, I'd guess it is hydrocarbon based. A propane/isobutane blend is the most common formulation, but other hydrocarbons in various ratios can be used. If it is in fact hydrocarbon based, it will be illegal in the U.S.

There used to be lots of discussion of alternative refrigerants, and even many folks rolling their own out of propane & camping gas, over at http://www.aircondition.com I think the bulletin board is closed, but the archived discussions are still available. Take a look at alt.ref if you're interested in this stuff.

According to their website, glacier Gold is distributed from Canada. It is not on the latest EPA approved refrigerant list. It is hydrocarbon based, according to the Glacier Gold website. The EPA specifically prohibits hydrocarbon refrigerants for automotive use. (Obviously EPA rules only apply to USA).

"It is illegal to use hydrocarbon refrigerants as CFC or HCFC substitutes in motor vehicle air conditioning."

http://www.epa.gov/ozone/title6/snap/ref.html#q06

A long thread on r/12 and r134a some time back discussed specific detailed problems with hydrocarbon based refrigerants - it should be in the archives for those interested in searching further.

R12 substitutes
 

All those products that claim to be a safe legal substitute for R12 are bogus. They all contain mostly propane ( which by the way makes for an excellent refridgerent). However it has never been approved by the EPA for automotive use. It is acceptable to a very limited extent in some industrial applications.

These products are highly flamable , dangerous, and will cause major damage to your automotive AC system over a period of time.

Whenever anyone tries to sell me any of this garbage I refer them to the following site.

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

BILL

moedep,

You hit on the phrase that I think you should focus on. If it looks too good to be true, it probably is.

These unapproved substitutes are bad for your system and worst of all are explosive. If you ever have a compressor fail, and make a spark, you and your car will be an instant car bomb.

For the sake of you and your family I urge you not to use this refrigerant.

I share your frustration regarding the availability and price of R12. I have a few pounds of it left and when it's gone, it will be gone.

I have already converted some of my cars to r134. I worry most about my 124 car. I am saving the R12 for it. It appears that now that warm weather is approaching, the 124 a/c system will make one more year.

You can either use R12 at it's exhorbitant cost, or change over to 134 which is not too tough and will work well as long as you don't live in a Houston type climate.

Best of luck,

While I would never advocate breaking the law or thinking that the EPA is anything other than the best environmental protection agency in the world, it is worth noting two facts. I learned on a boat refrigeration board that many household refrigerators in Europe use propane as a refrigerant. On that same board, a military person posted in the Persian Gulf reported that all the small fishing boats used GM automotive compressors and propane as a refrigerant to ice down their fish. And of course, Canadians would have no good ideas on what refrigerants to use since they live in igloos anyway!

I'm of the mind that any flammability risks from hydrocarbon refrigerants aren't worth worrying about. I'll point out there is no oxygen at all inside a properly serviced a/c system - hence no possibility of an explosion. If the system suddenly dumps its charge then yes. But lets consider that your car is already carrying 150lbs or more of fuel. In a modern gasoline car this fuel is pressurized to 35PSI or more at the tank and pumped to the front of the car. The engine is also filled with flammable engine oil, the brake system with flammable fluid, and if you drive an MB with self leveling...well, you get the idea.

That said, I'm not using them. They are illegal. My stash of R-12 is gone. Since my 124 wagon upchucked its compressor last fall, I've decided to try R-406a. It supposedly cools better than R-12 - a good thing if you're driving a 124 wagon in Texas. Will let you know how it goes after I get around to charging the system, and after if heats up a bit down here....

If you look at the EPA site, you will find that flammability is only ONE of the things EPA looks at in approving a refrigerant. Also, different refrigerants are approved for different purposes (marine, commercial chillers, etc.). Something not approved for one use is sometimes on a different approved list, as the hazards/pollution index/accident probability factors add up differently for different applications.

Also, nobody claims the EPA as the final authority on environmental issues (Some of their radiation regulations, for example, are ludicrous - coal burning power plants pump more long half life alpha and gamma radioactivity out their stacks than an n plant collects for burial. The n plant can't release anything, the coal plant is exempt! 50% of US power comes from coal, 17% from N plants. So which one is the environmental radiation source?) However, on refrigerants the EPA states their rulings are made solely on the basis of data PROVIDED BY THE MANUFACTURER, not by their own testing. The flammability, Hydrocarbon loss rates through non-barrier hoses designed for r12 only, the compressor life span effects, etc. are all from the refrigerant manufacturer, and therefore probably present a 'best case' estimate.

Finally, there is a large difference in flammability hazard between liguid gasoline and a hydrocarbon vapor under high pressure. Gasoline must be vaporized and mixed with air to explode, Hollywood notwithstanding. That vaporization must fall within a relatively narrow fuel/air ratio, otherwise it will be too lean or rich to explode. That vaporization occurs inside a nice safe metal cylinder head. Running tubing and connectors with highly pressurized hydrocarbons which may vaporize under the engine compartment is a different risk factor than relatively low pressure fuel lines from the fuel pump. A low pressure spray is less likely to produce an explosive air/fuel mixture than a high pressure refrigerant leak, which may have a lower flashpoint, greater volatility, and wider ignition temperature and fuel/air range than gasoline, as well as a different 'bang/cc' factor - it may have much more punch than gasoline! I have seen less than 1cc of toluene liquid produce a vapor mix in a fume hood accidently ignite from static electricity, despite safety use of safety cans and grounding straps. That 1 cc shattered the safety glass of the chemical fume hood sash, split the fume hood ducting, and was heard throughout the building.

Keep cool, but think safe.

Well Guys, all of you have a snap shot of the refrigerant issue correct. My Dad and I just did the a/c system in my 300SDL:
-Nippo compressor
-expansion valve
-drier
-both drier switches
-Freeze 12 refrigerant.
I'll tell you from first hand experience, this stuff blows better than any R134a vehicle that has retrofitted from R12. It's the best of both worlds. As long as you have esther oil in your compressor and system, you can use this stuff. I used 3-12 oz. cans for my system.
Compared to R-12, my money's on this Freeze 12 stuff. I paid around $8.00 with tax for a can.

FREEZE 12
 

JAY123
Congratulations: You just filled your AC system with propane.You now have about 12 months of use left on your AC system under normal conditions that is of course unless you get into an accident and blow up in the meantime.

I wish the federal Gov. would make an effort to arrest and penalize the vendors who supply this illegal and dangerous substance.

Bill

Please get your facts straight before posting misinformation. Freeze-12 is *not* a hyrdocarbon. It is about 80% R-134a. I don't know the composition of the remaining 20%, it is a refrigerant which is miscible w/ mineral oil. This is why Freeze-12 can be used in an R-12 system without changing to PAG or ester oil.

JCYUHN:

OK , but what is in that other 20%, and do you think its a smart idea to put at risk $1000.00 to $2000.00 of AC components to save 100.00 in refridgerent?

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?

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.

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.

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."

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... :)

the company replies
 

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.:D

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.

My first attempt to convert our 1988 W124 wagon (black w/black tint windows) from R12 to R134a, wasn't very successfull.

We only changed out receiver/dryer; expansion valve; and pressure switch, drained oil, and refilled 80% with R134a and the proper oil. On a 95-F trip to Las Vegas it cooled down to about 78-80 F.

This time, we evacuated everything, replaced the single pusher AC fan with the dual AC fans from a 1990+ W124 R134a vehicle, as well as the R134a specific condenser.

Also, replaced the viscous fan with a 16-inch SPAL puller fan at 2370 CFM.

Our trip to Las Vegas in 95-F cooled the cabin to a very cool 65-F.

In short, get more airflow with electric fans, and a high-flow/high-density condenser.

:-) neil

JCE, and others, Yall are doing a great job on this...

Manufacturers are able to say things that are technically true but that do not take into consideration all the conditions which may exist when the product is being used... for instance... FLOUR,,, plain old baking flour... does not burn easily... but you only have to see one grain elevator explode from a static electricity spark igniting the flour dust to realize that real world physics is a serious subject....

Thanks to all for taking the time to expound on this subject so well... Greg

the company rebutts
 

I emailed the company with more details of our discussion:

"1-2 lbs cannot actually compress inside the
cab of a merc. That couldn't even happen in Volks bug. That much could fit in a little can. Even if you designed an impossible leak which pumped, purposely every oz. into your cab with the
windows up, your entire family could still sit in that cab holding lit
candles."

"I am sure that all involved are just trying to be safe and we applaud that. be assured that hydrocarbons are safe. See the extensive work performed by Dr. Ian Maclaine-Cross of the University of New South Wales. He calls such scenarios impossible. It's as simple as that"

They sure did blow that 116 body up using freeze 12. Anyway the point is you get what you pay for so there is no miracle low price freon. You do the job right the first time or you work on it year after year . Logically it would be less expensive to fix the system properly the first time . Like I have said before ask the techs they have the most experience in this field. I can gaurantee the techs that have worked on mercedes most of their lives will tell you to stay away from this junk.:D

This is pointless. A compressed gas does not COMPRESS into a larger (lower pressure) volume, it EXPANDS into that volume. A compressed refrigerant will expand and difuse into ANY size lower pressure volume. If by no other mechanism than Brownian motion, it could expand throughout infinity, in theory.

When, during that expansion, a flammable compressed gas falls within it's LEL/UEL concentration range, it is a flammable or explosive mixture. The presence of non flammable gas may or may not be sufficient to permit that mixture from forming. I would presume that in the case of Freeze 12 it doesn't form or forms with such low probability that EPA allows it on the approved list.

I have not at any point stated that Freeze 12 isn't safe. If the EPA is happy with it, after consulting lots more than 1 researcher, then everyone is happy. If the EPA is unhappy with most automotive hydrocarbon based refrigerant applications (again, after consulting lots more than 1 researcher, and with public comment review, and National Science Foundation oversight committees, and peer review process) then maybe you ought to listen to them regarding pure hydrocarbon refrigerants instead of the people making money from the sale of pure hydrocarbon products.

The cigarette companies could find a minority of researchers 'proving' that their products are safe. But Science is done by majority consensus approval of all data. 'Facts' are accepted as truths until something blows them out of the water. Dissent is part of human nature, and people still calculate the value of pi, re-calculate the atomic weigh of Hydrogen, and debate 'established facts'.

Despite debate over the details, gravity still pulls, and Propane still burns, (and may explode) - it is that simple. It may not burn if other gases keep it so diluted that it can't fall within the LEL/UEL levels of concentration, or if no spark is present, etc. You can NOT safely extrapolate the safety evaluation for one mix of gasses approved for one application to every (or any) other mix of gases, pure gas, or different application. EPA, OSHA, NFPA, etc are in the hazards evaluation business. I did chemical, radiation, and biosafety hazards evaluations for 25 years, but if you are happiest with what the manufacturer says, then live long and prosper, for you have found Vulcan Kohlinahr, and need no other commentary. Nuff said.

If you look at JCEs profile, you'll see that he's a retired physicist.

That's close enough for me.

JCE - thanks for your input.

hey, just passing along their comments, perhaps its useful to see how these parties react to such questioning. I did invite the individuals from that company to respond for themselves here but in their absence i provide what they have emailed me.

No problems or bruised ego on this end. Maybe a little to forceful in making my point that manufacturers need to stay in business, and that the MSDS is a more reliable representation of facts about a product than web sites or sales brochures. You will make a choice that works best for you, and that is all that is needed. Enjoy the day! :)

JCE, I don't think you were too forceful at all, and I have been saying you were doing a great job on this subject...

Now, as John Lithgow says on Third Rock From the Sun " Lets get back to talking about ME "

So far.. in trying to overcome the physics challenged 134 cooling abilities compared to 12... I have come up with this list:

1. Be sure to be using the 9 bladed engine fan.
2. Use the parallel flow condenser.
3. Be sure the system is charged properly.
4. Use a bigger AC assist electric fan in front.
5. 134 Expansion valve (thanks Joe)

6. ?????????? Any thing else ???????????

Thanks, Greg

I've taken 2 of my old wagons, (88 124 and 85 123) and simply evacuated the systems, swapped out to 134 exp valves, replaced the driers and o-rings and blown in 134. With ester100 of course. I charge them a little different tho', start at 50% which is about 12 OZ and slowly blow in the rest looking for the lowest temp at the center vent, windows closed, recirc door closed and car fully warmed up. The 88 wagon in a shop that was about 85 deg F at the time worked itself to 44 deg F and Tom just took it to Texas and said it maintained 44 to 48 the entire trip. The 85 made it to 50 and maintains it well except sitting in traffic if the temp is over 90, it'll get into the high 50's then.

No changed were made to the basic system other than expansion valves. I did however seal the condenser to the radiator as well as I could.

On a 'nother note, I converted a 92 Lexus ls400 today (and guess what, it needed a evap) and it made it down to 48 inside the shop and today it was 95 deg in there when I charged it.

One BIG issue I've seen over and over are oil flooded systems and 134 systems seem to be particually sensitive to this problem. 2 OZ too much oil can raise output temps 15 deg's depending on the size of the system. Both of the wagons already had the red pressure switches for the aux fans so they were left alone.

134 aint a straight up replacement for good old 12 but, it'll do a decent job provided you run a 134 expansion valve, be sure not to oil flood the system and ignore that damn sight glass while charging. (I've noticed that around 2600 rpm the glass will clear on the ones I've charged by temp and paid attention to.)

One trick I use as well is superheat, put a temp probe on the suction line right at the expansion valve and charge it untill the the temp at that point is about 38F, the high side will be in the 240F zone at that point. Dont forget the old rule of thumb, on fresh air intake output temps that are 30 deg's lower are acceptable. And I've seen some that would barely do 20.

I'd run from the off the wall stuff due to too damn many potential problems with flammability and performance over the long haul. And a quick remark to the guy who feels shops overcharge for r12, bought a reclaimer lately? They aint cheap.


Joe

I've been reading this thread with great interest as I want to convert my W123 over to 134a. Some of you who have written on this thread have experience doing conversions. I'm not interested in hearing about "alternative" methods.....only R-12 to R-134A. So please keep the topic to 134A and not go off on these other ones.

Questions:

1) Does a person really need a parallel flow condenser?

2) What parts SHOULD be replaced when converting over to 134A?

3) Since my AC system isn't working right now, can anyone tell me if the aux fan is supposed to run when the AC is turned on? (240D without ACCS)

4) Any tips or advice from those who have done this would be great. I assume that the DIY can do this job without killing oneself. I guess what would be really great is if someone could run down the basic procedure of how to do this. Summer is coming and it gets into the 100s here in central California.

Thanks for the info.
mike

JOE P: Can you tell me exactly how much oil I should put in my '84 300D when I convert to 134a? And about how much gas?

MRWITH: Here is a quick review of what you need to convert to r-134a:

PARTS: all new (green) o-rings, new receiver drier, expansion valve, 134a-specific valves that screw on top of the r-12 shrader valves (I'm refering the valves with which you evacuate and fill the system), cans of gas, a bottle of oil

THINGS TO KEEP IN MIND:

-no matter how successful an r-12 system is converted, 134a will never perform all that well sitting in traffic. You won't start sweating, but you probably won't feel cold either.

- for lots of general information on this topic, start searching www.aircondition.com, which is a terrific webpage on automotive a/c

-the sponsors of this page, airsource.com and ackits.com, sell everything you need for your a/c system and are extremely knowledgeable

-one of these sources has rebuilt r-4 compressors for $134! Keep in mind that your compressor that has run for years on r-12 probably will not last long on 134a. THis is a somewhat debated issue, but the fact is, 134 does require higher operating pressures, and if your compressor is the least bit weakened with age or wear, you will find that it can't keep up with system demands, and the end result is you have bad a/c, and you are sitting there wondering what went wrong. I would just replace your compressor. If your system already doesn't work, it is probably already bad, if not just from sitting there from lack of use and oil starvation.

-DO NOT try to do this job without a proper vacuum pump and gauages. I happend to pick these items up cheap through the local paper, but a vacuum pump that will actually do the job costs around $300 new, and a set of gauges can be picked up at Pep Boys for around $50.

-Because you probably don't want to go to the expense of buying the pump and the gauges, I would recommend you replace all the components yourself, and then take it to a shop to have a vacuum put on it and filled with gas. Maybe you can check a local rental store to see if they have a vacuum pump??? If you are in the DC area I would let you borrow mine.

-As someone else mentioned, ignore the sight glass completely, it means nothing!!!! With a/c systems, the ONLY thing that means anything are the high and low side operating pressures. And this is why gauges are vital. You CAN NOT do real work on any car's a/c system without gauges. Generally speaking, you are looking for pressures around 180-190 high side and 30-40 low. But these pressures vary depending on the car and outside temperatures. High side pressures should be around 2.5 times outside, ambient temperature. Too high=poor cooling and death to your compressor, too low=poor cooling. Bottom line is? Get gauges, don't try to guess, and ignore that sight glass!

-in order to do the job right you need to blow out every component with a blow gun and mineral spirits. After you have blown the mineral spirits through and made sure it is comming out clean, blow just air through for a while to make sure all the mineral spirits are blown out and the component is dry.

-the best oil out there for a completely clean system with a new or rebuilt compressor is a Texaco HFC100. Get it at ackits.com. If you are using your old compressor with 134a, use PAG oil, NOT ester oil. The oils can be injected into the system with a turkey baster. All the o-rings need to be coated with the oil before installed.

-lastly, you do NOT need a parallel flow condensor. This was just my suggestion to the guy asking how he can optimize his system, but that is not to say your original condensor won't work too.

I think I covered everything. If there are any more questions, I will try to answer them, but you should really start going to aircondition.com, which is where I have collected most of my information.

One last fantastic info source is this saab technician's page (I am somewhat of a Saab feak too:) :

http://216.78.172.244/climate_control_folder/ac_retro.htm

and

http://216.78.172.244/climate_control_folder/acpressurediagnosis.htm

Hope this all helps.

Greg
'84 300D

Greg, great info...How many green oring seals are we talking about on your car ? Did you have to take the evaporator out from under the dash to install the 134 expansion valve ?

After flushing with any non 134 liquid I would suggest flushing with which ever type oil will finally be in the system until it also comes out clean... and keep blowing air until all of it comes out that will reasonbly come out.... Mineral Spirits , etc may have things which as residue would form gunk or acids...etc.... Thanks, Greg

123 exp valves are easy to get at, right under the r/h dash, just pull off the plastic trim and look up. I've seen a few oddball aftermarket systems that had parts in weird places but, most are right there.

4 o rings on the valve, 3 or 4 on the dryer, 2 or 3 on the condenser, most 123's use the York piston type compressor with the taperfit lines, no o rings, there are a few line joints under the hood that have o rings in them, replace them as well.

My wagon cooled well with the high side at 210 psi lo side at 33 psi, idle. The red switch throws the aux fan on around 225 psi which mine hit after 3 or 4 minites of idle. I ended up with 2 OZ of ester 100 in the dryer and thats all the oil that went in, if you's like, remove and drain the compresser, measure the oil that came out and replace with ester, same deal with the condenser. (most condensers hold 2 OZ except the monster in the 140 that holds almost 3)

I ended up with about 22 OZ of 134 in the 85. There again this is dependant on abient temps, air flow, evap size, condensor size and line lenght. Make sure the AUX fans work and your fan clutch is in decent shape. There again, I'd seal the condenser the the radiator as best as can be done without blocking the airflow over the radiator. (those little rubber seals on the 201 are great for this)

I've heard the storys about hoses that wick 134 through the walls and have never seen one leak that way with 134 unless it did it with 12 as well. Dont flip if you see 300 psi Hi side pressures as long as it dosen't get past that very far, if you freewheel the motor to 4 grand and it stays under 325, it'll be fine as long as your hoses are ok.


Joe

I'm going to buy a rebuilt R-4 compressor when I fix the ac system. My question is whether or not the new (rebuilt) unit will have oil (the kind used for 134A) in it already? Or, do they send them "dry" from the factory?

One last question. How does the Aux fan work with these A/C systems (W123 with R-4 and no ACCS)?

As for oil in the compressor - just ask the shop you are buying it from. They are the people who should know for sure.

From what I have gathered from this page, the auxillary fan kicks on when the gas in the a/c system reaches a certain temperature. There is a switch on the reciever/drier that senses the temperature. The bigger switch on the reciever/drier (the one about the diameter of a quarter), controls the compressor (turns it off if the gas pressures get too high or drops too low).

Greg

'84 300D

The last compressor I bought came empty... with instructions as to how much to add... but the one before that I had to try to figure out from the books at the part store, which sometimes list that stuff, and I never felt good about having the right answer....

I know some oil will be traveling through the system...that is what lubricates the top end of the compressor (and makes it not suitable for making into an air compressor) and some compressors have DIP STICKS to check the level... I wonder if it would be good to add the proper amount and see how much gets sent off..and around the system.. and keep checking until it stabilizes... which might be a while.. you don't want too much and you don't want too little....

GregS, you must be dealing with shops where the counter help is not perpetually on their first day at that job.... :) wish I could say the same... GregoryB

Just a update, I converted the ls400 and tried a new snake oil called "maxi cool" by interdynamics. I was getting 55.6f prior to installing it and shot it in, it went to 42.3f. Not bad, keep in mind this is a car with a less than new compressor and all r12 components.

I'll try this stuff again on the next conversion (83 300sdl) and let ya'll know the results.


BTW, I found the stuff at Advance Auto Parts.


Joe

R12 or R134A replacement
 

After reading many articles on alternate refrigirants, I finally decided to take the plunge and switch over to Duracool R12A.
I have had it for only about a month, and so far the ac system seems to love it. The air from the vent is much colder than before and I don't see a drop in rpm's at iddle when the ac compressor kicks in. That should translate in fuel savings and less wear and tear on the ac compressor and the whole system.
Why is this happening ?
From the manufacturer web site ( www.duracool.com) :
It requires about 35 to 40 % less refrigirant than R12 or R134A.
The compressor will run at lower pressures to reach cooler temperatures.
It is compatible with any oils.
It is capable of dealing with small amounts of moisture.
It is competitive in price.
Since the pressures are lower, there will be less chances of leaks.
The switchover only cost what it would have cost to refill with R 134A.
For me , it has worked. (so far)
jacquesrober

I don't know about Canada, but Duracool and the other explosive refrigerants are illegal in 18 US states plus the District of Columbia.

Best of luck,