JConn2299

Without getting into all the legalities, if your system isn't blowing cold enough and you need to recharge the refrigerant, it is much better to evacuate the system first. A vacuum sucks out all the moisture, air, refrigerant and anything else that's in there, and then the system is recharged with pure refrigerant and the necessary lubricating oil. This is preferable to just adding refrigerant under pressure.

moconnor

iTrader: (14)

Sometimes, yes - but this has nothing to do with the legalities of purchasing R-12.

A top up worked fine for me and would probably work well for most people unless their AC system has some serious issues. These issues would probably need to be addressed irrespective of what charging route they chose.

JConn2299

If you're concerned about getting the coldest air possible and the longevity of your A/C system, then you'll evacuate the system first.

Here's what another knowledgeable member wrote:

"BEFORE recharging the system with any refrigerant, I cannot overstress the importance of getting all of the air and moisture out of the a/c system. In order to do that effectively, you need a high vacuum. At room temperature that means at least 29.25" of Hg to flash out all of the moisture. Anything less will really not get the job done. A 28" vacuum, for example, will only remove 94% of the air. Air cannot be condensed in an A/C system and will get trapped at the top of the condensor resulting in loss of efficiency and higher than normal compressor discharge pressures."

https://www.rx7club.com/showthread.p...8&page=2&pp=15

bajaman

Yup.....Section 609 of the Clean Air Act. Here in Kansas they STRICTLY enforce this when you try to buy 1 pound cans. In fact, the O'Reilly's and AUTOZONE parts stores have this law prominently displayed above the counters.

Now, after spending some time reviewing this information (you piqued my curiousity!) it appears to me that a private individual need not have to supply any recovery system equipment information. However, in another place on the Kansas Small Business website it mentions that farmers must have recovery equipment to purchase BULK refrigerant....sigh.

Now I wish I'd have bought about 20 cases of the stuff when they were getting ready to regulate it. I well remember Wally-World advertising 24 can cases (as many as you could carry!) for $19.99.......and now the stuff goes for $30 a can when you can find it!

moconnor

iTrader: (14)

So a private individual (who is probably much more likely to screw up) does not need proof of a recovery system but a business does. Seems ***-backwards, but a lot of EPA regulations are. The EPA exam is way too easy (can be done in 10 minutes or so after spending and hour or two reading a perparatory manual) and has no practical component.

There are dozens of cans for sale at any one time on eBay. I plan to stock up later in the year - it will eventually be very rare.

NCMontegott

iTrader: (5)

yes you are correct in that manner. i was referring to both refigerents in bulk form as in 20 lb containers that i deal with at work. but if you were to convert to r134a it is going to cost you money no matter what you do.

NCMontegott

iTrader: (5)

you can take an online exam to certify you for purchase of r12

bajaman

Well...now that we have hijacked this thread completely....

Here is some interesting information from a place that sells refrigerant:

Production of R12 or CFC-12 was halted by the clean air act on January 1, 1996. Today the remaining supplies are product which has been recovered and reclaimed back to a chemically pure state in accordance with ARI-700 standards. The ARI standard is basically a virgin specification. The supply of virgin product is limited as most of the virgin was depleted in the first and second years after production ceased.
PRODUCTION CEASED IN 1995

http://www.r-12.com/


Now I have heard from various sources that most of the "R12" you find on places like eBay is anything but "virgin" and in some cases is so contaminated that it has been known to cause fire hazards in cars it was put into. Evidently Mexico and other non-scrupulous 3rd world countries have been foisting this stuff off on to the unsuspecting public for a few years now.
Most A/C shops now have testing equipment that determines the level of contaminants in bulk containers, and initial reports are that a high percentage of what is labeled as "virgin" is in fact corrupted with butane and other hydrocarbon-based gases, sometimes as much as 20%!

I think the old caveat 'Let the buyer beware' is appropriate in this case. I am much more comfortable finding a can or three at garage sales......

Mr rx-7 tt

iTrader: (5)

http://www.freeze-12.com/

Mr rx-7 tt

iTrader: (5)

So has anybody used the Freeze 12? I want to change from 134 back to r-12 or something as cold. 134 isn't cool enough.

Nathan Kwok

I had the conversion done and honestly I couldn't tell the difference, even in 90+ degree weather the car still cooled perfectly fine. I suppose if I went from 35 degrees to 40 degrees thats still way colder than I need. I asked my mechanic about the conversion hurting the cooling and he said the problem is much worse on marginal systems...