69er

My rebuilt unit is leaking on the hood above it and seems to be getting worse and worse.
Rebuilts don't last is what I hear so I'm biting the big $$ bullet for a new one.
My question is being I'm going with a new unit should I stay with the 134 or is there something better available now that would work with a 134 setup?
The 134 has been ok.
Just wondering.


[Modified by 69er, 9:51 PM 7/21/2003]

Smokehouse69

R-12 is better than R-134, but it is too expensive for my blood, especially as leak prone as these systems are. A buddy of mine spent several hundred dollars on a new compressor, drier and R-12 only to have the evaporator blow out 4 months later.
I've already bought what I'm going to use in my system, it isn't exactly DOT approved for auto A/Cs in the U.S. but it is legal in most of the rest of the world. It is a hydrocarbon based coolant called Enviro-Safe. 6 oz. Enviro-Safe is equal to 18 oz of R-12, and puts a less of a load on compressor and less drag on the engine. It also cools better than R-12. You can find it at http://autorefrigerants.com/co00033.htm

69er

"Enviro-Safe refrigerants are perfectly compatible with both R-12 and R-134a systems. The 22a and the 502a are ultra-efficient replacements for R-22 and R-502. There's an Enviro-Safe alternative to any of your current refrigerants. They work beautifully with most types of A/C system lubricating oils"


"These products get extremely cold and extend compressor and other A/C part life. It has a perfect product liability record and several million very happy customers. It is manufactured and bottled in The United States of America. "

Steve
Seems like a good replacement for 134.
Seems the 134 set up is ok.
All that has to be bought extra is the R-134 hose adapter for their cans.
How many cans would I need if I go with Enviro-safe?

Smokehouse69

My system says that it need 3.75 lbs of R-12 for a full charge. That's 60 oz. of R12, and if one 6 oz can of Enviro-safe is equal to 18 oz of R-12, then you'd need 3 1/3 cans of Envirosafe.
I ordered a case of 12 cans of the stuff, and sold 4 of them to another 'vette guy. I figure the 8 cans I have left will charge my my system and give me 5 cans to spare. I bought the stuff last year, when I though I might work on the A/C this past winter. Well the engine swap and associated stuff took up all my winter time, so I'm seriously considering breaking into the system this summer. It's already too hot to drive the damned thing in the daytime, even with the top town the sun will par-broil you really quick. So I guess a couple of weeks to pull the dash, replace heater core, replace broken center duct and reseal everything should be do-able.

69er

Interesting stuff,Steve.
Will definitely consider using it.
I like the fact no changes have to be made to the r-134 set up and Enviro-Safe™ Refrigerants can extend equipment and component life by lowering compressor “head pressure” up to 33%.

Thanks Steve :cheers:

Larry B.

Joe.. Here's the downside to anything exept R134a or R12. Mosts shops won't touch them because they are not equipped to handle them. Next, they are blended refrigerants so when (sooner or later) they leak, one of the components leaks first because the molecules are smaller. So now you can't just top it off because the ratio isn't correct anymore. If you can't find someone to evacuate the system ...... I'd stay with R134a. It's easy to get, cheap and works fine. The biggest problem is getting the exact correct charge. You want less than the amount called for. Go for 26-28 psi on the low side. That may only be about 2 1/2 cans.. I found the "sweet " spot for mine and it is working great. Actually our older systems seem to take the R134a conversion better than most.

69er

Now you have me thinking,Larry.
Seems the Enviro-safe product has some better points but down points too. :cheers:

Dalannex

I think you guys should hurry up and get that Enviro-Safe conversion done so that you can tell us all what you learn along the way and how it works. I am running 134 in my 81' and it works well, but like the lower system pressure idea. Make sure you post a topic once you get the conversion done. :yesnod:

-Justin

69er

I'd love to,Justin.
But now I don't know which way to go! :confused:
In any case it won't be done for a couple of weeks.

OHSIXX

I have had no problems with R-12.

69er

R-12 is $70 a can if I can find it round here.
I do hear ebay has cans now and then but I made the 134 changeover.
I've also hear there's only 1 country left making R-12.
Will be hard to get soon I would believe.

69er

After Larry's post and talking with a few people in the automotive repair field including a A/C guy I'm going to stay with R-134a.
It's the standard now and also readily available.
Seems the Enviro-safe refrigerant may have the unit cycle more because of it's low pressure.I think that's what was said..:confused:
Steve let us know how it works.I still may do the change if you see a noticeable difference. :cheers:




[Modified by 69er, 11:40 AM 7/23/2003]

Juliet

I just had the AC restored on my '70. I went with a product called 'Auto-Frost'. It's a blend of several refrigerants and not too costly. It's working fabulously! Infact it actually worked so well it froze up the system with 1" of ice on the lines when driving with AC on max in 99% humidity on the caravan. ;) It hasn't done that since. I had my original compressor and other components rebuilt and brought the whole thing up to Tony's Corvette to get working. He's the one who recommended AutoFrost. He's been using it on all his customer's cars for about 2 years now with great success. The vents blow about 40 deg on a 95+ deg day. What a luxury in a roadster. :cool: :cheers: :yesnod:

69er

Hi Juliet.
I have to check if AutoFrost can be used with my R-134 changeover or for a R-12 setup..


Just did some internet research on AutoFrost and came up with this.
http://www.heco.net/TheTruth.htm

About half way down the article it states

Blends with R-22 are a problem with seals designed for R-12 and/or R-134a. These blends will cause seal failures, even though some are EPA SNAP approved (or approved for use in Canada). R-22 will chemically attack our regular seal and cause the rubber boot to disintegrate.

We have identified the following blends that contain R-22:
R-401A, MP39, R-401B, MP66, R-401C, MP52, R-405A, G2015, R-406A, GHC-X3, R-409A, FX-56, R-409B, FX-57, MP33, Kar Kool, ICOR Hot Shot, McCool, Chill-It, GHG-X4, Autofrost High Performance, and Monroe Air Tech Autofrost.

Because new alternative refrigerant blends containing R-22 require barrier-type hoses, non-barrier-type hoses must be replaced with barrier-type hoses increasing the expense of retrofit.

This information is taken from the IMACA (International Mobile Air Conditioning Association), Red Dot News Bulletin, Climate Control (York Compressors), and Parker (receiver-driers).

:(


[Modified by 69er, 5:35 PM 7/23/2003]

Skeets

This is interesting stuff!

I've got to re-charge my R-12 system soon and was gonna go with R134 (my A/C guy says there is a R134 that he can put in without having to change any seals) ... however, i was a bit concerned that it wouldn't work as well as the R12 (already, it's not the COOLEST system).
... some of these other products sound pretty good, and might even improve my system :cheers:

..... keep posting the latest updates guys!

OHSIXX

Anything wrong with just staying with R12?

Larry B.

Any refrigerant system works on rapid expansion of the gas entering the evaporator. you must mantain a temperature above the frost point or the system will freeze up and block the air flow. 38 degee air is 38deg. air regardless of which refrigerant is producing it. The pressure/temp relationship of R134a and R12 are almost identical. R134a will replicate the R12 low side at about 26-28 psi. The high side will be slightly higher but not enough to make any noticable difference. If the temperature is higher than with R12 then the system is overcharged. R134a will not work as well if you use the same amout as R12. The biggest problem with R134a is overcharging. AND it is very sensitive to the correct amount when compared to R12. Since converting leaves some old oil in the components and each car is unique, there is not set rule to go by.... whatever works is what you need. You don't need different compressors or set-ups. Just use ester oil, get the correct amount. make sure the condenser is clean and the heater door is closed. R134a is just as good as R12. :cool: