Maxi Frig refrigerant for old AC? Is It Real?
 

So I found this stuff on E(vil) bay. You can go to their website http://www.maxifrig.com/blog/ and it is even cheaper. Has anyone tried this stuff? I am about to unless I can find someone who says it's crud. It says no Vacuum is required and is recommended. WHAT? No flushing. HUH? Just put the stuff in and your COOL! Seems like hogwash. Although 10 years ago I was just trying to see if my repair on my Toyota held pressure so I did not pull a vacuum. Just put one of those aerosol type bottle of refrigerant cure all in and it is still cold today. I did however replace all the goods on my wife's identical car and pulled the vacuum and did it all the way your supposed to and it is better than my car but was a serious pain! The expansion valve was not working blah blah. Any way, For 12 cans for $60 it is as cheap as 134 at Wally World.:waah: Someone tell me not to do it....

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

I read somewhere that it's mostly propane, for better or worse..... probably not the best idea but I guess it does work, dunno how well though or if there are issues. There are some old threads here, a search might be in order. Same goes for stuff called Freeze 12. Doesn't help you much, I know, sorry. Hope you get better replies from others, I just recall reading there are problems.....

I went to the trouble & expense of converting to r134a, all new parts but it's finally good now. Only took three shops, three new compressors, and one year of my life. :waah:

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Someone from Down Under can correct me, but my understanding is that propane is what is used in Australia for automotive air conditioning. It's still a greenhouse gas, so I'm not sure how "green" it is, per se. I'd have to go research it.

R-134 is a greenhouse gas, though. It is 1,1,1,2-Tetraflouroethane, in which the Fluorine holds on tight enough not to be a problem for ozone depletion like R-12, which has Chlorine. Still, greenhouse gases are a problem. We should have just learned how to keep on sweating!

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Anything other than r12 or r134 for our AC systems is snake oil.

I restored the factory AC on my 68 to oem specs and r12. It has blown snowballs for over a year now in all weather conditions; it works flawlessly. Do it once, do it right when it comes to AC.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Propane or R290 is the best replacement for R12 next in line is Hot Shot 1 that I have used. I have used both for friends to good success. At this point I have not used a product designed for cars as I have access to commercial grade stuff.

Propane is by far the cheapest, and easy enough to install. About $2 to fill a average system. Nearly every current common refrigerant is based on a hydrocarbon aka flammable. They add in some retardents so they do not catch fire so easily, and even if you use just propane. The amounts that a system contains only catches fire in dramatic ways like you see on YouTube if you make it do it. The soft hoses under the hood is where 99 percent of the leaks reside.

Car systems are far less susceptible to lack of vacuum then typical commercial compressors so it is not completely nessacary but still a very good idea to do it.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

I may give this stuff a try. If it works it may save us all! R12 is expensive and bad for the environment.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

folks ride around with 20-22 gallons of highly flammable liquid either behind the seat or under the bed and now they want to get all worked up over a few ounces in a sealed system under the hood?

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Well I ordered it. Stay tuned. I was going to buy an extinguisher anyway. Some real old wiring in that car.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

I had an old Toyota that took R12 so I tried "Freeze 12" when r-12 became hard to find and expensive. It worked once or twice then the seal blew out the front of the compressor. I replaced the compressor (junk yard) and it blew too. I did some research and the manufacturer notes in the fine print that you MUST have a high-side "relief valve" because the head pressure gets very high. -BA

This was not stated on the can. It was on their web-site at the bottom.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

I pay $10 a can for r12 on Craigslist, that’s less than r134 at Walmart here :lol: I used 4 cans, $40 and a year later still working. Anything you put in there that it isn’t designed for will not have longevity and you’ll waste more money fixing it later. Even doing a 134 conversion takes several times to “get it right”. Again, money wasted thinking it’s cheaper than r12. Bad for the environment? :haha: Millions of cars on the road burning gasoline are doing far more damage to the environment than r12 ever has or ever will.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

This one says the head pressure is much lower. I will use my gauges when I install it to see if that is correct. Since the weights are not the same, I am thinking I will put just enough in to get cold air and see if that will work. What's the harm. It doesn't work now.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

If you use propane, what oil do you use?

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

I work in commercial HVAC so I am not up on what is going on in the car field.

None the less we used the same oil that was in the compressor when bought the new parts. So 4 years later it is still going strong.

In commercial the oil is dictated by the equipment, and not the refrigerant. Now we use a lot of POE oil since it has better return rates to the compressor compared to mineral. Which is real important on a split system with long line sets.

So the way I understand cars oil return is not a issue since the line set is around 5 foot. Not the 50-100 foot that is common in commercial work. Plus car evaporators kind of run flooded compared to stationary units like commercial. So the liquid refrigerant helps move the oil back better compared to vapor.

Either way just use what they have in your truck.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Does the maxi cold use the same PT chart as R12? Or does the refrigerant have a larger glide.

What I would do is barely fill it like you said, and drive around to test. Maybe you could get a go pro camera, and mount the guages so you can monitor pressures as you drive.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

I find that sitting in the driveway doesn't really tell you much. Driving and getting good flow through the system tells you more. I guess I could combine both my gauge sets to make real long lines and look at the gauges while driving would really tell the story. But then again, that would be like texting and driving. Then again, and again, the Bel Air MUST have cool AIR! COOL AIR MAN!

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Run a large box fan in front of the condenser to simulate driving conditions.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Looking at the properties, it appears to be more like R-22, which doesn't work in R-12 systems as well (I think). Anyone from Oz with AC charged with propane aware of any differences?

ETA- Found the answer. Propane is not allowed for automotive AC in Australia. Don't know how I got the previous information.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

You can just buy R290 which supposedly has retardents in it for flammability or so I have been told. It is legal to use. They sell it at a couple of local supply houses I go to just sitting there on the shelf.

If it is like R22 it will work fine but when it warms up. They have a tendency to trip on high head or blow seals. At a 100 degrees R12 is about 80psi lower then R22.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Hmm. I have a big jug of r22 just sitting there. Now I may have some Maxi Frig just sitting there. I just want to be cool.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

That's good to know. As soon as I find and repair the leak in my truck's AC system, I'm going to use the last of my 30 pound tank of R-12. If I can buy R290 without a license, that will be nice.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

If your going to use R12 I would replace all the hoses and o-rings. Being that you have an older truck,and easy to work on comparatively.

It is cheap insurance as if one hose is leaking on a older truck the others are not far behind.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

A woman I dated for a bunch of years dad had a Masters in Chemical Engineering and worked for Dupont in Millington, TN for 40 years told me the banning of R-12 was because the patent to R-12 was going to end allowing competition. They lobbied the Govt. to outlaw R-12 while Dupont held the patent on the new R-134 replacement Freon.

Back in the late 90's I bought Mexican R-12 and sold it for a profit. I also bought a Snap-On refrigerant recovery machine and made agreements with various junkyards and tow away lots to suck out the R-12 from the cars and trucks being stored. I remember some of the crap I'd end up sucking from these cars. The Freeze 12 and other DIY crap was lining the shelves at the parts stores. I found that stuff incompatible with real R-12 and can understand some of the sludge and failure to cool problems.

Not much call for R-12 anymore. Mainly some purists that don't want to alter a classic. Just squirting some crap in your system isn't a problem solver and actually may cause more problams in the long run.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

I was going to put this in my 58 Bel Air to see if the system was worth trying to save. It has what I believe to be a period correct retro fit ARE kit with an underdash type unit. It has hose clamps on the hoses. It has something in it just not sure what. It still has the old R12 fittings on the York Style compressor. BTW would I use the top or bottom fitting for charging?

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

Follow the hoses until you find one on the suction side of the compressor. The low side port should be between the condenser and the compressor. It may well be on the compressor itself, if memory serves me correctly, on a York compressor. If so, they will be marked so that you can tell. Whatever you do, make sure you don't try to charge on the high side port. Reports of exploding cans were common among do-it-yourselfers, back in the day before different size ports were used to avoid that problem.

Re: Maxi Frig refrigerant for old AC? Is It Real?
 

That's some of the same discussion our supervisor had with us. I work in food service refrigation and we are building many propane refrigerators for McDonalds. Talk has been of slowly phasing out 134a,1234yf is an upcomeing refrigerant, we use mostly 404 and propane now. The propane charge is significantly lower ounces than regular refrigerant.