Speedway1

I need to charge my system a little. Can I add Freeze 12 to the R-12 in the car or does it have to be purged to add Freeze 12?? If so It would be easier I guess to add R-12 if I can find some.

zr1fred

If it just needs less than a can, no problem. If the system is almost empty, change to the 134. You can get the kit at most auto parts stores. It's just an oil charge, couple of cans, and the fittings. All C4's work fine with 134. Check the shrader valves, (where you hook up the guages) they tend to leak there.

Speedway1

Not sure how much it will take. It kicks off and on about every 10-15 seconds.When the car is hot it seems to stay off more.

kelc317

I thought you couldn't mix R-12 with 34.I thought i read somewhere that you had to do something to get all the r-12 out before adding 34 or it could cause some sort of problem?

Muffin

If you have a system that is reasonably sound why not have an AC shop add the required R12? With the increased cost of 134 and the current availability of recaptured R12 I doubt there is a significant difference in cost.

zr1fred I just checked the Freeze 12 web site. They do not say R12 and Freeze 12 can be mixed. Freeze 12 acts like R12 in use, same oil and pressures but mixed, don't know. Do you have a reference?

Speedway1

I may just add r-12 .

wro87

Go to the nearest shop and have them add the R12 lot less PIA. the local dealer added a can for $25 bucks and since 87' have only had to add not quite 2 cans in all those years.

Good Luck wro87

hooked073

To answer the OP no you cannot just add freeze12 to you R12 system they are 2 totaly different things. The Reason for R12, and why it took years to come out with 134 is they are a single modcual agent. Meaning if you loose some you know that you only losted one agent and can top it off. If you fill with freeze 12 or a lot of the other non certified refergent they are multi modcual so if you loose some you do not know if you lost moducal a b c ect. so you can never top them off. Fed law also requires you if you know or have changed your refergent that it be labled. If it is not labled and damages accure you are responable. I will also say if it is not 134 or 12 The only way I will do a repair is trash the compressor. Flush everything and start over.

Frizlefrak

OK, I'm confused. What does "modcual" mean?

socalman

I think he meant molecules-

hooked073

Im sorry dog Brain not working well today you got me molecule.

Siveck

My latest understanding of Freeze 12 is that it is some form of R134 made to be used in place of R12. I would use R12 since it is available. It can be found for a semi reasonable price. Your system will work better and last longer with the R12 since it was designed for that refrigerant. If your compressor is cycling, then you are probably about a can low. Buy a can or two on ebay or craigslist along with the R12 fill hose that has a guage. Make sure to jump the low pressure switch when charging so that the can won't explode when the compressor kicks off. Check the FSM for the proper procedure and pressure or let us know if you need that information.

hooked073

I they do their job as sellers you have to have a hvac license to by R12.

Siveck

Good point. I took the open book test online. I think it cost $20 and took a couple of hours. Now I am certified to buy R12. It is very educational as well.

http://www.epatest.com/609/

hooked073

I got certified in 84 back then it is a 6 hr class then a test LOL. But it was more about the reclaiming and recycling more then anything. They were preping everyone for the change over to 134. And before then reclaiming was not manditory.

Frizlefrak

Ahhh....guess I should have figured it out from the context.

zr1fred

Hooked073 is technically correct. However, in the real world, thousands have used Freeze12 (a chemical cocktail) in their R12 systems without problems. I'd guess hundreds of thousand systems have been changed to 134 without changing the compressor without experiencing problems. As a matter of fact, the availability of R12 is due largely to most people (do it yourselfers, and to a lessor extent, shops) just changing over to the presently excepted standard (and readily available without hassle), 134. Most cars after 1985 are designed to work with 134. 134 tends to leak out (gradually) of old systems because it's molecules are smaller than R12. The oil problem comes in because 134 does not transport oil as well as R12, so a different oil is used, and it is designed to be compatable with the old oil to a large extent. The 134 and so called "drop ins" have been out for so long, it's hard to find a non corrupted R12 system. One of the problems with compressor failure is due to not recharging the oil after a serious leak.

Speedway1

OK,I just got a can of R-12 put in and A/C works fine but my fans are not running.Does the switch on the line beside the compressor sitch control the fans?? I unpluged the switch and my fan started but the one in front of the condenser is not running. Can I just change the switch if its the problem without loosing all my R-12????

SunCr

Aux fan (in front of the Condenser) isn't linked to the a/c and should never come on unless there's something seriously wrong with the a/c.

A/c fan switch is on the high line (and the one you disconnected). It opens at around 230 psi which means the ECM voltage reference rises and with that, the ECM drives the Main Fan. When the pressure drops to 190 psi, the switch closes, the reference drops to Zero, and the fan is turned off. You need a Manifold Gage set to check whether it's working right and an ambient that's at least above 50 degrees. As designed, idle/low speed head pressures should average about 200 psi with the fan cycling on/off to keep it there. As a side effect, idle/low speed Coolant temps should be 8 to 12 degrees lower than the non a/c threshold for fan operation. If it isn't working this way, something is wrong - air flow, plugged up coolant passages, overcharged or plugged up a/c system.

Siveck

Yes, the switch has a shrader (sp?) valve under it on the line to keep the refrigerant in while you change parts.