Reid Fleming

iTrader: (2)

I imagine my situation is pretty common around here. Old R12 system that's been pretty reliable since day 1, but not cooling as well as it used to. The two basic choices were:

1) Find R12. Local shops were a waste of time. Oh no, we don't do that. That's illegal. We only do R134a.

2) Pay about $500 for a proper R134a conversion. Then deal with constant leaks and poor performance.

Neither seemed too appealing. I wanted something as cold if not colder than R12 and better for the environment. After much research into alternative refrigerants and safety/EPA certification, I decided on Autofrost.

It's a blend of R22, R142b, and R600. Best of all, it uses the same oil as R12, so no problems with compatibility, corrosion. No oil change needed. It comes in 9.6 oz cans and you're supposed to use 80% of the R12 amount. 80% of 2.25 lbs works out to 1.8 lbs which is exactly 3 cans. Perfect. It charges through an R12 hose which is handy as well.

Took the car in to a shop and had them hook up their evacuation/vacuum machine. Sucked out all my R12 and ran a vacuum for 30 minutes. Cost around $70 or so. Not too bad. Went home, grabbed all my Autofrost stuff and installed it.

Since it goes in as a liquid, you put in up to 60% in to start. For our cars (R12 = 2.25 lbs) Two cans = 53%. Easy enough. Then you start the car and let it idle for 3-5 minutes. With the GM CCOT system it's better to let it idle a bit longer. So I did around 6 minutes or so. Upon first starting the engine, the compressor clicked on..off on......off. on...............off. I could tell it was circulating through the system.

At this point I reached my hand in through the open driver window and THIS IS COLD! I haven't felt air conditioning like this in years. I grabbed my temperature gun and pointed it at the duct. It was going right down to 22°F before the compressor would cycle off. The compressor was cycling off at 26 psi and on at 47 psi (if memory serves me correct).

After 6 minutes had passed, I put the 3rd can in and the cycling dropped down to a minimum. The can says use low or high for the first 60% and then the last 20% in the low side only. I recommend using the low side for the entire install. I put the 3rd can in the low side while the car was running. (Installing through the high side with the car running will explode the can and cause injury)

Using a temperature gun isn't really a good way to measure duct temps as they're constantly changing. I've been using a metal temperature probe that just sticks into the duct. (If you're married, you can steal your wife's temperature probe from the kitchen) My first drive it "only" got down to 35°F.

I guess the stuff was still working it's way through, because every time since the first day (a few weeks ago at this point) it's gotten all the way down to 31°F. Now that is some serious air conditioning.

The stuff costs about $10/can. Figure $100 to get your old stuff evacuated/vacuumed and the new Autofrost purchased.

They claim that R406a has a faster pull down temperature upon initial turn on compared to single refrigerants. By the time I leave my neighbourhood (about 30 seconds) I'm already at 40°. It takes a bit longer once you start getting below 40°. But not that long. Three or four minutes perhaps.

When I tell people about the temps, they all say isn't that too cold? Why would you want something that cold? I'm of the mindset that air conditioning should be COLD. Not just for the cooling, but also for the dehumidification factor. Something that goes to 50° will cool you down but you'll never feel particularly cold. And you'll sweat all summer long since the coils won't get cold enough to really evaporate the moisture. Duct temps in the 30's will.

I highly recommend Autofrost (R406a) for anybody who has an R12 system that wants high performance air conditioning while still being good to the environment.

pizza_guy

My only issue with your report is the "constant leak/poor performane". I'll beg to differ if actually done properly. Well, and the fact it's not really fair to compare your non-optimal a/c(why else would you touch it?) to your now freshly vaccumed and charged system.

The fact you had your system vaccumed down is the biggest thing that people don't do that leads to poor performance. If they only understood how an A/C works...

Great write-up. If it works, I don't see why to not use it. I prefer my R134a though, becuse when "Autofrost" goes under/gets sold, I won't care.

And the can's instructions of "high or low side" is gonna kill somebody someday. Glad you took note of this and brought it to attention.

wannafbody

iTrader: (1)

Guess I shoulda done more research befor buying frezze 12

di11avou

iTrader: (1)

Actually if you look at the MSDS, it's a blend of R142b, R22 (Used in residential applications and also scheduled to be phased out), and Isobutane. I'm just not a big fan of putting flammable substances in my A/C system.

atomicskr

R-12 is readily available off of e-bay. That's what I use.... no muss.... no fuss. Just presurre check for leaks (I use nitrogen). The evacuate, vacuum, and shoot it. Ice cold A/C for less than you would think and done in about an hour if you've got all the tools!

Reid Fleming

iTrader: (2)

I'll admit there are many ways to do R134a. Everything from the $5 Wal-Mart kit to the professional A/C shop version that costs hundreds of dollars. But the duct temperatures themselves are the key to what really works. I haven't seen a R134a system that goes below 45° yet. I'm sure they are out there (full size trucks with huge condensors?), but for our cars, I don't think R134a could touch an Autofrost system. Personally I want the best or I don't want it at all.

My 4th gen Z28 has had the (R134a) A/C done twice by the dealer in past years. It doesn't work now at all! Hence why I noted the poor cooling/leak that 134a seems to exhibit. The GTA hasn't had a thing done to it since new (R12). It was still working albeit poorly (50° duct temps).

As for the vacuum, I wholeheartedly agree. You could hear it sucking the stuff out standing next to it as it ran. And it's such an easy procedure to do. The evacuation machine was also a vacuum machine. Gave me extra time to yack with the shop mechanic about cars.

The R600 is isobutane, I'll admit. But it's 4% of the mixture. Helps with the oil return. I wouldn't want to run straight propane like some people do. All sorts of "questionable" alternate refrigerants out there on the market too. Hence why I went with an EPA certified refrigerant. 4% of 1.8 lbs is 0.072 lbs of isobutane.

I don't think there will be a problem with R22 for awhile. Even R134a is supposed to be phased out in the future. R22 is strong stuff. The guy who invented Autofrost had a slightly stronger version of it called GHG-HP back in the early 1990's (more R22 in the mix) that would blow duct temps in the 20's. Ice fog coming out the ducts. Cold enough that it felt like it was burning you. That stuff is not made anymore and illegal to use. It needed high pressure cut out switches and cycling compressors to really work right. Variable displacement compressors would ice up hence the need for some sort of defrost timer. Must have been nice to start up your car and turn that on when you're sitting in gridlock traffic in Miami or some place hot like that.

Another benefit of having duct temps as cold as I'm getting is that the air feels so much better to breath in compared to 40-50° duct temps. It has that same feeling you get when you step outside in the winter and temperature is hovering on freezing. You can feel that cold dense air go through your lungs.

For the price of R12 cans, it costs about the same to ditch it and go R406a. Honestly I'm not even sure if R12 is or isn't bad for the environment. But why not go with something that's known to be clean for sure? I've always thought it's strange that you can drive a 1974 or older car every day with no catalytic converter and it's legal, but you can't put 1 lb of R12 in your car.

johnsonm

Can you disclose where you got it and how much it cost? Is that allowed?

Thanks!

Reid Fleming

iTrader: (2)

Autofrost is available on Ebay. Costs aprox $10/can. You'll need an EPA 609 certification to be able to buy the refrigerant. You can get the certification from www.epatest.com

I see you're from Florida. *Whew, wipes sweat from forehead* This stuff must be worth it's weight in gold in a hot humid place like FL.

johnsonm

Hey Reid,

You said this stuff WILL install with a plain ol' R-12 charge hose and can fitting?

I got my 609 certification and ordered several cans and all needed A/C parts. I was just studying up while wating for things to arrive in the mail and noticed a couple places said "unique fittings required".

What did you end up doing?

Yeah, it's pretty hot and humid down here in sunny La Crosse! I have kept the air working in my wife's truck, but it has been several years since I have had A/C in any of my cars. I finally broke down and bought all the parts necessary to fix all of them. I'm pretty excited!

Reid Fleming

iTrader: (2)

You have a few options in regards to the fittings.

You can keep your old R12 fittings and simply connect and recharge.
or
You can put on the special Autofrost fittings. (Proper EPA way to do it)

The Autofrost fittings are a two part system. There is a skinny fitting that goes over top of your original R12 valve (let's call this #1). And then there is another valve (#2) that fits over top of that, that has an R12 valve on the end of it.

Pressing the valve stem on #2 will press down on the valve stem on #1 which will press down on the valve stem on the original R12 valve.

Pictures are here: http://www.refrigerantsales.com/autofrost.html
The pictures on top are "#1" and bigger pictures below are "#2"

They're only about $5 or so. Might as well get them. I did.

naf

iTrader: (7)

If you're seeing below 'freezing' supply temps it's a good sign that your evaporator is freezing over. As the moisture is 'sweated' out of the air it can freeze over on the coils, reduce airflow, impede heat transfer, cycle liquid coolant back to the compressor, and so on..all bad.

Your pressure switches may need adjusting, especially with a change in coolant.

Reid Fleming

iTrader: (2)

Interesting take on things.

The strange thing about the pressure switches is that the Helms book says on at 45 psi and off at 20 psi. I think 20 psi is too low. I'm getting 47 psi and 26 psi respectively. When I first measured it, I thought it might actually be cycling off a bit too high. Maybe bump it down to 24 or so. But I left it as was and thought I'd road test it.

Raising it to say 30 psi would reduce the symptoms that you mention. But on the other hand, it would mean a lot more cycling which isn't that good for the compressor anyways.

I've heard of people getting 38° in humid Texas and 33° in dry Nevada. Basically I think it comes down to that this stuff was just flat out meant for extreme cooling. Yes, I'm getting down to freezing and even a tiny bit below. But not that much below. The variable compressors like the V5 probably have more of a problem with icing up than the cycling ones do.

100°F in Texas /w Autofrost (not me): 38-40° duct temps.

For comparison, I drove through Texas with R134a in 100° temps and was getting 55° duct temps.

naf

iTrader: (7)

The pressures given by the Helms manual are for the original coolant.

Your compressor is mechanically driven, cycling is a major issue with electric driven compressors, high amp load start up w/hot windings, etc.

It's not the coolant that determines the delta t but the system. You've replaced the original coolant with one that has different properties. Below freezing supply temps are an indicator of a problem. R12/22/134 are capable of producing the same below zero temps, the system is just not designed to do it.

Next time you're on a long drive allow the A/C to run high continuously. If the compressor is not cycling off and you begin to notice diminished air flow you can be certain the coil is freezing over. If it's cycling and only producing below 40 temps occasionally, you're probably fine.

johnsonm

Are pressure switches adjust similarly to knock sensor? Tighter = more sensativity???

How does one go about adjusting pressure switches?

Thanks!

Also, the evaporator is burried deep in the dash, if one were ambitious, I guess you could access it to visually check if it were icing up??? Correct?

pizza_guy

THANK YOU!! This is what I've been telling people, and they seem to think I'm crazy.

I use the following analogy: "It's like putting ethanol in your gasoline-designed engine." It's obviously not going to be the most efficent setup.

And about factory R134a systems being sub-par...our LO3 engines are considered sub-par from the factory, but people don't blame the gasoline, do they. Instead, they modify/tweak the factory engine to increase output. Instead of learning about how A/C works, they use these "marketing gimmiks" and gripe when they find out...wait for it...the advertisers fudged the numbers. I mean, how many people actually believe X part gives them X hp just because the marketer said it would.
--------------------------------------------------------------------------------------------------------------------------------------------------
The pressure switches are just that. They are electrical switches(on/off like a light switch), except they are triggered by the pressures in the system. These switches perfom a balancing act to keep your A/C running properly. Until you learn how an air conditioner works and get a gauge to measure your system pressures, I wouldn't mess with them.

I'll give a very basic diagram to get you started.

Accumulator: This part holds the low-pressure coolant not "in use".
Compressor: Takes coolant from Accum. and compresses it to high pressure. This heats up the coolant, like a turbo/supercharger heats up the intake charge.
Condensor: The radiator-type device that cools off the high pressure coolant.
Metering device: These can vary from system to system, but it meters the high pressure coolant into the low pressure side. On our vehicles, an "Orifice tube" is used. As the pressure drops, the coolant cools off, exactly the opposite of the compressor. Since the higher pressure side was cooled off, this tempreture is now much lower than the ambient temp.
Evaporator: Another smaller radiator-type device the transfers the heat from the air to the very cold coolant. It cools your air.
After the evaporator, the coolant goes back to the accumulator and waits to get compressed again.

For space and sanity sake, I left out some of the smaller details.

naf

iTrader: (7)

And ONE of the problems with converting an R12 system to R134 is that 134 requires a larger coil to work most efficiently. Yes, it will work, but the system was designed to work more efficiently with a different coolant.

I'd have to dig into adjusting the switches, been a LONG time since I did it. I'd probably just put a guage to it then turn the switch til it cut out. You know, the old fashioned way.

johnsonm

Right, got the gauges, have a pretty good basic idea of how the refrigeration system works, now here to learn some of the details, like how to adjust the pressure switches.

Can using a refrigerant other than 134 still be an appropriate way to do things, as long as you make all the necessary tweaks and adjustment to they system to get it to run as optimally as possible? Or is using r-12 or 134 the only appropriate way to get a cold a/c in old Firebird?

I am flushing the system, changing out seals, have a "new" rebuilt compressor. I didn't really want to change the condenser, so I was looking for a refrigerant that was supposed to have more similar cooling properties to r12 than 134.

Am I totally misguided?

ghettocruiser

iTrader: (4)

The evap isnt burried deep in the dash. Its accessible through the firewall side of the HVAC box. Just a series of little screws and the top lid will come off, exposting the evap core.

Wouldnt be hard to see if its icing. Just install the cover with a few screws so you can take it off quicker to see if you have ice. Water can start to ice up at 37*F...so at 31* I imagine its freezing pretty quick.

This pic might look weird because the front half of the box is 4th gen and the evap is 4th gen... but it still shows how you can access it..



this thread was pretty interesting. Since Im using the newer 4th gen a/c system, Im going to stick with 134. I gotta get it vacuumed down and see how it works. It blew ice cold while it was in the 99 camaro...so I see no reason why it wont now.

Good stuff!!

Justin

naf

iTrader: (7)

I would go with 134 to replace the 12. It's properties are very close to those of R12 and it doesn't require a permit to purchase. It may not be the closest to R12 any longer as several new types of coolant have come onto the market in the past few years, including this 406a.

Another concern with using blended refrigerants is fractionation. I don't know if 406a is azeotropic, meaning the different molecules are of similar size and would leak out in similar quantities (in the event of a leak). A zeotropic refrigerant would leak out in disproportionate quantities, changing the overall properties of the remaining blend and requiring a complete evac/recharge in the event of a leak. I'm showing off now, of course.

I've heard that swapping out the evaporator coils with a later unit designed for 134 can be done but I'm not sure it would really be worth the effort. Orifice should be swapped out along with all the o-rings. Vacuum before re-charge of course.

Reid Fleming

iTrader: (2)

R12 at 20 psi would probably be about the same as R406a at 26 psi.

I tried using NORM instead of MAX this afternoon. Duct temps sat at 41°F and stayed there. Still pretty cold. About what I remember the car being like when it was new. But turning it over to MAX gave that super comfy blast of air that actually made you feel cold (and I had a T-shirt, sweatshirt, and jeans on).

I don't think long term use of MAX and low 30's duct temps is going to be much of a problem. Reason being you just can't run it that cold without getting too cold yourself. During hot sticky days, the ambient temperature should probably make the system run that bit warmer that it shouldn't be an issue anyways (see TX at 100F above). As is right now, I generally run the A/C for about 10 minutes and then switch to vent.


It is a zeotropic mix (all the R400's are). Azeotrophic are R500's.
I've heard people on both sides say yes this is bad because you need to evacuate the entire thing. While others have simply topped it up and been satisfied with it. I will give the single type refrigerants like R12 and R134a the nod for not having to worry about this.

Going on a different topic for a second. One thing about air conditioning I've noticed is that there are so many different bits of advice. Lots of good and lots of bad. On this very board there was a post saying that 58°F duct at 100°F outside was "cold." Another post said that 55° was optimal and that anything colder would be uncomfortable to the driver. Pffft. Yeah right.

naf

iTrader: (7)

I think you're probably fine with those duct temps.

You did make me look something up though. Pulled out a manufacturer's informational guide for 410A. It's listed as "Near Azeotropic, Does not fractionate easily". The guide also notes that it will fractionate under charge if drum is not positioned to deliver liquid. Don't have a guide for 406A, it's not a coolant used in any of our systems. It's really a moot point though as fractionation isn't really a concern with a small system like in an auto. Mainly a concern for commercial systems that hold a substantial amount of coolant. Like I said, I was just showing off and am by no means an expert.

johnsonm

naf, are you in the refrigeration business? What is 410A? What do you use it for?

Reid, how long have you been converted to R406 now? Any of your peeps use this stuff before you and convince you of its virtues or did you stumble across it on your own?

I guess you used the stock orifice tube when you converted? (Still directed to Reid)

naf

iTrader: (7)

Nah, I'm in facilities, new construction and maintenance. Got some HVAC techs that work for (with) me though. My background is civil. 410A is one of the newer coolants intended (by the manufacturer) to replace R22. I had the guide on my desk because we had to purchase a new manifold set for it recently. The discussion was probably getting a little off topic there.

johnsonm

Probably, but real world credentials may add or detract relevance to a post.

Reid Fleming

iTrader: (2)

R410A is the newer environmentally friendly refrigerant that home HVAC uses (as well as commercial I would guess). On the home front it's R22 or R410A. The top of the line Lennox Elite heat pumps use R410A. I do believe it has a higher pressure during use compared to R22.

johnsonm, I used the stock orifice tube. I had previously read about the Ford "blue" orifice being a good idea, but just wanted to try Autofrost as it was. See how it worked on a completely stock system.

I'm in Canada, so not much use of R406a around here. In fact even the A/C shops in town hadn't heard of it. (Understandable as they want you to spend hundreds on a conversion to R134a) I did a bunch of research on the net about how to best go about getting an R12 system up to snuff. Read about the different kinds of refrigerants out there as well as the good and bad. I was originally going to go with Freeze 12 as it's a well advertised replacement. But once I started reading about what it's made of (mostly R134a) and the lackluster duct temps, I shied away from that. You can get good performance from Freeze 12, but it means setting the compressor cycle off at around 15 psi. That just looks like a recipe for disaster. 50F duct temps with a normal compressor on/off cycle psi with Freeze 12 seems like a bad way of doing things. Heck, I was getting 50F with my R12 system that was cycling every 5 seconds.

I've read a fair amount about home A/C and the troubles that new homes in the south have had with high SEER units not dehumidifying as they should. They run the coils warmer as a way of "saving energy" despite the fact that a warmer coil won't dehumidify the air. Thus brand new houses in TX/FL are getting mold all over the place. It only stands to reason that a warm duct running A/C in a car will do the same. I don't want cool and clammy. I want cool and dry.

When I read about Autofrost and how it used the same mineral oil as R12 and actually would carry the oil around the system unlike most of the other replacements, it peaked my interest. The colder duct temps and low cost but not low performance aspect drew me in. The guy that created this stuff seemed to know what he was doing.

With my car, I never like to go half effort. I want the best or I don't want anything at all. With the Autofrost it really looked to me to be the system to go for. I read a fair amount from the inventor of it about how it was fairly easy to get certified for industrial use as an R12 replacement but at the time took a few years to get certified for automotive. Basically there was a huge lobby group about only wanting to use R134a. There was A LOT of money to made in expensive conversions that are incompatible with the old system. I can sympathize. When was the last time you saw an ad for an R-12 replacement in an automotive magazine? Seems like a few years after the R134a changeover, they finally started letting R12 substitutes onto the market. In Canada, most R12 systems that are in need of fixing aren't fixed. Since A/C is used rarely, nobody bothers to spend the big bucks to fix it. You just buy a newer car. And with the low use of A/C repairs, that means the shops can charge that much more to do the change over. I didn't want to pay $500 for a system that would cool as good or possibly a bit worse than a good R12 system. Consider that Canadian cars don't use the A/C as much as an Arizona car and you understand why the seals wear out from under use. When I read about people on the board getting their cars converted at shops for $100-150, I can only shake my head and wonder if I'm getting ripped off or if they're getting poor work done. Possibly a bit of both.

The average joe can't even buy R134a at places like Wal-Mart here. You need to be certified and even then you can only buy it locally in the big 30 lb cylinders. No small cans anywhere.

I've had quite a few people with old R12 systems who have been curious as to how it works. The shop that evacuated my R12 and vacuumed it was very curious as to how it worked out. How long it would last. How cold it "really" would be. The manager there who I know quite well mentioned that R134a prices have been going up and that the big cylinders even with their purchasing power was getting quite expensive. We all know manufacturers claim R12 performance for $10.....but in my case it was true. From the inventor of R406a I've read that below 80°F outside it gives R12 performance while above that it gives 4-13°F improvements. (Depends on the system...TXV? Orifice?) My experience so far has been nothing but good. Granted, I've only run the system for about a month. But I've talked to a few people in hot hot climates over the last year who say this stuff is THEE stuff to use and not to bother with Freeze12 or R134a. Also seen countless people who haven't been happy with R134a conversions (usually people in humid places like Georgia, Texas, Florida etc).

I was tempted to just pump it up with R12. But I'm a stubborn guy when it comes to emissions and environment. Heck, I put all the AIR tubes back on after I did the SuperRam conversion. And then I did plugs after that. Kept the EGR, put a brand new cat on. So for me to get R12 and better performance with an environmentally friendly refrigerant that also just happened to be 1/10th the cost of R134a, hey why not go for it? Seriously after putting this stuff in the car, I wonder why it never caught on in the first place. The only answer I can see is that most people just haven't heard about it. You'd think A/C shops in Florida would be selling this stuff like hot cakes.

My experience with R134a hasn't been that good. Repaired it twice in the Z28 and it came from the factory with it. That was at GM dealers so it wasn't some rinky dink hack job either.

naf

iTrader: (7)

Ried: Don't misunderstand me, I was not arguing against the use of 406A, just pointing out that the change would likely require some adjustments to system settings. You seem to be having great success but it still may not be working most efficiently without adjusting pressure settings and maybe a proper orifice, etc.

The only reason I would recommend 134 over another coolant right now is because it is readily available and there's more experience in its use...you know the pressure settings required, orifice type, o-rings, etc. If you want to do a 100% change over the mechanical pieces (coils, etc.) are also readily available. No reason not to experiment though.

Reid Fleming

iTrader: (2)

I understand what you're saying naf. I've actually been thinking about changing the pressure settings around. I wonder if something like 35° duct temps would be a better idea. The trouble is that the low 30's temps are addictive. Once you get that, you don't want to go back.

I think I might have a go at taking the evaporator cover off and taking a look at how things look under there after a long drive with the A/C cranked. Shoot my temperature gun at it and get a reading. On the other hand, I haven't noticed huge piles of water dripping out after parking, so I don't think it's icing up that much.

rideon1200

Alright, A/C man here. R22 will be phased out in 2010. Right now most of your "ligitimate" havc co are only selling 410a. Also, most A/C are being made with 410a. Autofrost or whatever comes under diffrent names. It is also called Hotshot or R414a. It is used in low temp applications and is not going to be phased out. It is a drop in replacement for R11 and R12. If you put 80% in you have nothing to worry about. The reason that auto dealers do not use is they like to make 800.00 on a conversion. There is a huge profit margin in this and not much to do. If you just put 134 in you current system it will crap out in weeks due to drying out the gaskets. Also the oils are not compatible and your compressor will be gone in no time. Have seen this many times. All refridgerants are flamable. When burning they release toxic gases. When charging you car witch the big line. It should sweat but not ice up. Also compressor should not kick out. Best to find a A/C truck in your area and offer 20 bucks ON THE SIDE to recover refrig and vac system. He could also help with purchase of HOT SHOT and proably even put it in.
----------
Dont mess with pressure setting or expansion valve. You will only screw it up. There is no need to change pressures with drop ins.

92GTA

iTrader: (11)

Hey guys....

I'm trying to buy some of this stuff to put into my GTA. Upon searching however, I cannot find "Autofrost" or "R406a". I did a search for "Hot Shot" and found it but it comes up at R414b. I then did a search for R414a and found some under the brand name of "McCool".

So which do I buy?! Lol. The "Hot Shot - R414b" or the "McCool - R414a" ??? Or should I keep searching until I can find some actual R406a???

Can someone maybe please explain the differences in these 3? Thanks!

EDIT: I bit the bullet and bought the "McCool - R414a" because I found an eBay auction for really cheap and that didn't require me to have the EPA cert, plus it was free shipping! I'll be taking a trip to an A/C shop to have my current system evacuated correctly and flushed/cleaned before I put the stuff in. I made the mistake of putting in R134a without a flush but my A/C only has about 1hr of run time since letting out all the R12 and putting in the R134a. I'm assuming these cans all have a standard fitting on the top of them? P.S.: Tell me I made a good choice! Lol. Also it looks like I need to add oil to this??? So I may need an A/C shop to fill it too? I also read that I need new seals and "barrier" hoses?

http://cgi.ebay.com/ebaymotors/ws/eB...m=220129233862

EDIT AGAIN Crap! Look at this posted by the inventor of Autofrost:
http://www.aircondition.com/wwwboard...rent/7083.html

It says:

"We had setup a blending plant for McMullen Oil products in
Brookville, FL to make R406A/R414A, which they made for
a couple of years as Mccool 406A and "Chillit" (R414A).
A number disputes, namely poor quality control, such as not
pulling vaccuum on cylinders to get air/moisture out and not
paying patent royalties caused us to deauthorize/delicense them
after 2 or 3 years. They were also caught putting 30 lbs
of product in cylinders DOT approved to handle 25 lbs. Their plant
also had their UL certification revoked also (R414A is UL listed
under the tough 2185 standard). If you run across any Mccool R406A, R414A, or "Chillit" it may be old product still floating around from a few years back. I would be real leary of the quality, since we are no
longer associated with them."

Grrrr....

92GTA

iTrader: (11)

Well I'm going to go ahead and pay for the stuff and go ahead and use it and see what happens. It sounded like most of the QC issues were with large containers and hopefully not these small cans.

Since the thread starter did not mentioned that he changed any seals or hoses, I'm going to stick with my factory stuff too since I'm broke, lol. I'll simply have the A/C shop flush clean the system and fill it using the R414a using regular oil like what R12 uses since that's what Autofrost says to use.

Reid Fleming

iTrader: (2)

Hey there.

I'm starting to wonder if this very thread has made the Ebay Autofrost supply dry up. Probably temporary. Do a search for "Frosty Freeze" and you'll see the company that I bought it from.

There are a few people on TGO that have used Hot Shot and had good results with it. One of the differences between Autofrost and Hot Shot is the oil return. http://www.autofrost.com/oil/index.html Keep in mind this is from Autofrost's website, but you get the idea.

Personally I'd use Hot Shot before R134a. How long Hot Shot lasts in a car? I don't know. Maybe the difference in the oil return means it lasts 5 years while the Autofrost lasts 10? From what I've read on TGO, the people using Hot Shot find it to be fine. Still much easier to deal with than the incompatibilities that the R134a changeover requires.

I didn't change any seals or hoses or orifice. GM cars have used Barrier hoses for quite a while now. All I did was evacuate the R-12, run a vacuum for 30 minutes (probably should have gone for more, but 30 is the recommended minimum time). Paid special attention to the install (percentages, amount of time during install, etc in my 1st post)

Today and yesterday the temps were 90° outside. Yesterday I was in a Lincoln (R134a). Measured the duct temps on the highway and in the city. 50° was where it sat for the majority of the time. Occasionally going to 51, sometimes down to 47. It's a 2000 model year. It was "cool" (not cold) and the car had enough insulation and solar tint that it wasn't too bad. But I felt a bit clammy. (not cold enough to dehumidify that well) This was on the AUTO setting. Manually selecting recirc didn't result in any difference (I'm assuming the auto setting had it on recirc most of the time. It doesn't let you know if it's on fresh or recirc when in auto mode)

Today, same temperature, I had the GTA (autofrost) on the road most of the afternoon. It was still getting down to the low 30's although I did notice it would head up to 40° at long stop lights on the highway or 42 long stop lights highway with traffic in front.

It also cooled down waaaaay faster when initially starting the car.

I measured the condenser temperature when I got home (car idling in the driveway with MAX A/C on, laser temperature gun) and it was 160°F. Coolant temp was in the mid 190's. (I have a 180° thermostat).

Despite the GTA being black with black leather (HOT) and feeling the heat coming through the roof (hardtop), the interior still felt light years more comfortable than the Lincoln.

Xophertony

if you only got a days use out of the R134a you may have allready ruined your stock R12 seals. i would replace them with new r12 seals before putting in your new refrigerant. you will just leak it all out in a few days. seals could not be that expensive. buy new ones and have piece of mind.

have your system evacuated.
install new seals
have your system "vacuumed" to remove all moisture let in from you cracking open the system to replace the seals
install new refrigerant

enjoy low temps in car. don't lick the windows, your tongue will get stuck.

92GTA

iTrader: (11)

Alright so I guess I'll be ok with the stuff I bought then?

I'll look into where to buy a set of R12 seals for my car and try and get them installed. I'll also try and have vacuum pulled on my system for as close to an hr as possible.

I'm still unclear if this stuff still needs to oil added and how you install it since it's a liquid? I guessing I can't use the same kit I used to install the R134a because that hose and gauge won't fit or work or what?

Thanks!

EDIT I called my GM dealership and they gave me 2 P/N's for the seals that I need. 2724577 - Hose seal kit, & 2724954 - Compressor seal kit. Are those the only seals I'm going to need?

BTW, I don't think my old ones gave up because my A/C still works but I want the piece of mind so I don't have to do this again for a while.

johnsonm

I bought some off e-bay from Frosty Freeze products. The sale said he had 12 cans available, I bought 7. So ???

DO NOT buy the special adapter hose from the same place, it is total crap. It leaked from both the tap end and the end that connects to the accumulator. The threads on the AutoFrost can are right handed (or left handed, which ever one is opposite of normal, righty loosey).

DO GET an old fashioned R12 clamp on hose. The kind that fits over the ring on the top of the can, and has a little cam lock on the side, that tightens up against the opposite side of the top ring. (not the clamp on, belly tap) This one fits on the top of the can. I forgot those still existed. I think you can use them on just about any kind of can. I got one at AutoZone for $9.

Becuase of the leaking hose, I think I only got about 75% of what I needed in the car, and I'm sure it fractured or separated or what ever it does. But, with all that, I get duct temps just over 40*. My compressor cycles quite a bit though.

We'll see, this was all kind of an experiment on my part. The air never has worked on this thing since I've had it. It is for now.

92GTA

iTrader: (11)

I just came from my local auto A/C shop and they want $120-$130 to "scavenge the system and put it on vacuum". They said scavenging it alone just to get all the old stuff out would be $90 and then the rest is for having it on vacuum for 1hr. I told them exactly what I needed that it had the remaining R12 vented, R134a installed without any kind of a flush, and that I need the entire system cleaned out so that I can install R414a.

I originally had gone to the A/C guy I always go to but he said he did not have the correct equipment to scavenge it correctly to get all of the oils out and he recommended me to this other shop that wanted the $130. That price seems a little steep so when I get done with that I'm going to go back to my old guy for possibly having the seals replaced and to have him fill it with the R414a, he seemed really curious about the stuff.

I'm also reading into the "Dry-Pak" and the "Cryo-Silane" that's sold by http://www.cryochem.com The guy that invented the R406/R414 stuff HIGHLY recommends using it. I think for sure I will use the Cryo-Silane but i'm not too sure about the Dry-Pak stuff and if I really need it after having the system vacuumed. If anything I think I'd need it to inhibit any moisture that occurs before the Cryo-Silane kicks in and seals everything.

Comments?

92GTA

iTrader: (11)

A couple notes on the Cryo-Silane and the Dry-Pak.......

Obviously the Cryo-Silane will only work when there is 0ppm moisture content inside the system. This means that for the Dry-Pak to achieve that, the system must not have significant leaks and also that the drier be replaced no matter what, that way the Dry-Pak is not wasted in the drier. Even if vacuum is used for an endless amount of time, the dryer should still be replaced.

Autofrost used to make R406a WITH both Cryo-Silane and Dry-Pak already in it BUT they have not for over 13yrs Cryo-Chem only sells Cryo-Silane and Dry-Pak kits for R134a and R22. These kits are already pre-mixed with the refridgerant. That means neither kit can be used by us with the R406a/R414a. Even though the R22 is compatible, it would change the ratio of R22 in the R406a and that is not acceptable I imagine.

Autofrost recommends obtaining Cryo-Silane and Dry-Pak straight from Cryo-Chem in naked form so that it can be added maually. I sent Cryo-Chem an email about this yesterday and also quoted Autofrosts recommendation. I await their response in regards to selling these products naked. If I can, then score, big time!!!!!!

That means I'll be evacuating and scavenging my entire A/C system. Replacing all the hose and compressor seals with GM R12 ones, replacing the drier with an R12 GM unit, and then putting vacuum on the system, adding the proper oil, filling the system with 2 cans of the R414a I bought along with the Dry-Pak, running the system for awhile, then I'll add the 3rd can of R414a along with the Cryo-Silane. After a couple days the Cryo-Silane will do it's thing and my system will be tighter than a virgin nuns couchie, be bone dry, and efficient as all hell hopefully. Speaking of, at this point it should be blowing cold enough to freeze hell over I hope

I'll post back in regards to what I hear from Cryo-Chem.

92GTA

iTrader: (11)

Well I just got off the phone with the man that invented R406a/R414a, George Goble himeslf. Talk about an enlightning conversation!

I also spoke with Cryo-Chem and one of their distributors in WA.

Here's the scoop......

Dry-Pak & Cryo-Silane in "Neat" form cannot be purchased anymore. George said I should buy the Cryo-Chem R134a version kit of the product with the Tune-Air (AKA Dry-Pak) and Cryo-Seal (AKA Cryo-Silane). It comes with 1 4oz can of Tune-Air and 1 4oz can of Cryo-Seal. The kit runs $190 from the distributor I spoke with in WA, wow! George says that adding these version that are already premixed with the R134a in the can is just fine. He said just to be sure I do NOT get neoprene seals (the green ones) and that I use real Mineral oil ONLY, not ester oil or anything else. He said so run it with 2 of the R414a cans along with the Tune-Air for 20-30mins, then to put in the last can of R414a and the Cryo-Seal. He said having the extra R134a that's premixed with the Cryo-Chem stuff won't matter one bit, SWEET!

So, being that this Cryo-Chem stuff is freakin $190, I think I may look into buying a new compressor too. I'm already going to replace my seals and dryer and it was mentioned the lines should already be barrier type, by replacing the compressor too atleast i'll have piece of mind that all this crap won't just leak out ASAP wasting all the $$$ I just spent. As it is my system takes about 2 years until it gets so low it won't cool as well and kick on due to the low pressure switch so I really doubt I need a compressor or seals but seals are cheap and I don't know what running the R134a from autozone may have done to my compressor in the 2hrs of runtime it has.

Talk about getting expensive. Atleast I'll have like the baddest A/C possible in a 3rd gen, lol. That right there should be worth it when it's 115 degrees outside!

DJK90IrocZ

I know that this is a very old thread....but the company that is making Autofrost, is no longer going to be making it. Since Autofrost is a blended refrigerant, one of the types is not going to be available from their normal supplier anymore.

I was planning to use Autofrost in my R12 stock system....guess not anymore.

hmx

IIRC, HotShot is similar in compostion to AutoFrost. HotShot is still being made and is available from IROC I think.

Beware to read the labels, though. There were a few 'replacement' coolants out there that were a mixture of R-134a and something else, and I have heard nothing but bad news out of them.

Hot Shot:

R-22: 50%
R-142b: 9.5%
R-124: 39%
Isobutane: 1.5%

AutoFrost:

R-22: 55%
R-142b: 41%
Isobutane: 4%