Calling all A/C guys and gals

[Steve P.]

A long while ago I had heard something about R-12 refrigerant NOT being a problem with pollution or any sort. After hearing some of this buzz for a short while it stopped and I never did hear if the USA is allowing the everyday use of R-12 again.  So this is question 1).

2) Would using a correct 134-b system be more efficient using R-12 and other than changing the oil to R-12 safe oil what would it do? I know 134b pressures are higher but R-12 worked well on both high and low pressure systems where 134-b is very picky.. 

Teach me...... 

[Ghoste]

I am nearly 100% certain that R12 is still illegal.  Once you're on the EPA deadly toxin list that is where you stay.  As for your second question, hmmm?

[teamroth]

It is illegal, and is being replaced as we speak. The main problem with the cfc and hcfc refrigerants is that people release them into the atmosphere. This would not be a problem if people didn't release them. They work great. Propane works great and so does ammonia, however both have their negative sides...Ammonia being very toxic(the stuff we use at home is anywhere from 5-10%, the refrigerant form was/is about 95%, deadly.)
And propane being flammable.


The EPA hasn't made it easy to dispose of the stuff yet. It's supposed to be incinerated, but there aren't many places that do it.

I am leaving work now, but will get into this a little deeper tomorrow. I actually just drug out my 50lb refigeration book....lol

[Rolling_Thunder]

R-12 = illegal...     Replace with R-134A

R-12 makes for cooler temps but a good R-134A system will make 33-34*F   

[Steve P.]

Again, what I had heard, (or at least thought I had heard), was that R-12 was NOT the big problem they thought it was. I know they are still selling it all day long in Mexico.

I do not have a way of testing the consumption of the 2 systems, but it sure seams like the difference in my fuel mileage is really big when I am not using the A/C. I go from a bit over 10 MPG to nearly 12 with the A/C off. This is figured over full tanks of gas. Not by the goofy calculator above the rear view mirror. Now if it were  30MPG to 28 MPG drop I wouldn't much care. BUT 12 to 10 is huge when you only GET 10!!!!!  

[Steve P.]

R-12 makes for cooler temps but a good R-134A system will make 33-34*F   

Not where I live... Hot and humid 8 months of the year. The other 4 months are just humid.    My system is up to par and I keep a vent thermometer in the center vent year round. Also my truck is a Florida addition with extra insulation in it. All the glass in a super crew doesn't help either. The best night time temps I have seen were in the low 40's. Nasty days I see 56 - 59*. That's using MAX all the time. My system has been checked by a buddy in the business and by the local Ferd dealer A/C tech. And you KNOW they want to sell you something!!!!!

[Steve P.]

Was just about to clap my hands for ya Bull, but you pulled your reply.

Here is what I just found at AllPar.



Automotive air conditioning and R12 updates (R134a and more)
What the future brings: new refrigerants

Some information in this section is from Automotive News.

The home mechanic, looking at a can or two of R12 or R134a, may think that government concern over refrigerant is overblown. However, CFCs like R12 have been found high in the atmosphere, where they destroy ozone (since CFCs have been regulated, the ever-widening holes in the ozone layer have been healing themselves). Likewise, a/c refrigerants have proven highly effective at trapping heat, increasing the possibility of man-made global warming; R134a is said to be 1,400 times as effective at trapping heat as carbon dioxide; a few leaks from a few cars
would probably not have any serious impact, but there are an estimated (by the auto industry) 400 million mobile air conditioners out there.

Europe is planning to phase out R134a due to its relationship to global warming. Carbon dioxide is the current E.U. leader; it's the least powerful greenhouse-gas, but it must work under very high pressure, and is less effective than engineered refrigerants. While new cars will use carbon dioxide, R134a will probably still be produced for older cars, avoiding the currently extravagant prices for R12.

One replacement under study, R152a, has heat-retaining power just 10% that of R134a, but is still a good refrigerant (unlike carbon dioxide). Another new refrigerant being developed by Dupont and Honeywell would be a "drop-in" substitute for R134a, but would trap less than 10% of the heat as carbon dioxide when in the atmosphere. No timeframe for availability is available yet.

There have been two major types of air conditioning refrigerant in North America: R12, "the old kind," and R134a-based, "the new kind." (R22 was used briefly as well in the early days.) Today's air conditioners seem less reliable than the R-12 units of old, and repairs are very expensive as key parts are buried deeply in the car. Still, R12 had a clearly demonstrated link to holes in the ozone layer, with clearly dire effects for the future. R134a was adopted, and many say it was adopted because DuPont had a patent on it. Australia uses a cheaper and more efficient refrigerant system.


Go figure...

[John_Kunkel]

Steve P and I have made the same observations, those who claim R-134 is every bit as good as R-12 are citing ideal conditions. Even if R-134 will sometimes produce near-freezing temps it takes a lot longer to do it.

Take two identical vehicles, one with 12 and the other with 134 and set them in the sun to hot soak for several hours on a hot day. Fire 'em up and see how long each takes to reach a near-freezing temp. If the 134 vehicle is a retrofit the time will be longer yet.

[flyinlow]

The first place any refrigerants including 134a should be banned is any vehical or building being used by Al Gore.

Lead from the front!

[RD]

R12 is still being sold by autoparts stores, but only to certified techs. so technically, it is not illegal persay, just illegal for non-certified technicians to install it.

[bull]

Was just about to clap my hands for ya Bull, but you pulled your reply.

I don't even remember posting here.

[moparstuart]

R12 is still being sold by autoparts stores, but only to certified techs. so technically, it is not illegal persay, just illegal for non-certified technicians to install it.

we recycle it here , we have a R-12 machine and a 134-a machine .  Pumps it out of the salvage cars and filters it and pump it back in cars we do a/c work on .      R-12 is not illegal yet , to those aproved to install .

[John_Kunkel]

It's worth mentioning that the 609 license to buy/sell/handle R-12 is available online. It's an open book test.

http://www.epatest.com/

[Chatt69chgr]

It's pretty easy to take the test and get a license so you can buy R12.  The actual R12 is expensive.  I think that if you have a license, the EPA can come out and see if you have equipment to recycle the refrigerant.  If you don't you better be able to prove that you took the car down to a place that does have the equipment and had them suck the old refrigerant out of the system before you worked on it.  Not worth all the trouble.  Best to just convert over to R134A.  Not that hard to do.  To do it right, you have to replace the hoses, O-rings, and get all the oil out of the sytem.  This may require replacing the compressor but most replace the old RV2 with a Sanden since it's so much more efficient.  You have to replace the receiver dryer since it can't be cleaned but they don't cost much.  The unit to cycle the compressor is sold by I think bouchillon and classic auto air.  By converting over to R134A you can add the occasional can of refrigerant since auto systems all lead to some degree.  Also, I think the refil on the refrigerant is you use about 70% the amount of R134A compared to whatever your system took in R12.  But that would assume you were using the same compressor so probably wouldn't work if you were changing to a Sanden compressor (and new evaporator and new probably different length hoses).  Determining the amount of R134A to use on a new system that you have put together yourself is a bridge I havn't crossed yet.  Any air conditioning mechanics out there with the answer to this?

[400/6/PAC]

http://www.aa1car.com/library/tr497.htm
I use hot shot or freeze 12 for R12 replacement.
There is a problem with fractionation as these are a blend of several different refrigerants.
Automotive systems do have a chance to leak but if the system is in tact it should not leak.
The link above explains fractionation and Lot's of other info about Automotive refrigerants.
The link also talks about Bootleg R12 from Mexico and gives a lot of info on refrigerants.
It can be very costly to retrofit R12 systems to 134a.
I have found that hotshot and freeze 12 have the same cooling characteristics as R12 and are a lot less expensive than R12 but do require an EPA certification to purchase.
Retrofitting to 134a is the most recomended thing to do but comes down to how much do You want to spend up front and will 134a give You the desired cooling.
I have bought 12 OZ cans from NAPA and O'really