I just decided to share this knowledge with you.

What you already know.

When switching to R134a it's best if you flush the system. Don't Flush the Compressor, just drain it's oil.
Switch all O-rings to 134a Compatible rings.
Replace Orifice tube
Replace Accumulator can
Lower turn off pressure on Low cutoff switch on Accumulator. (Small screw between the terminals back it out almost a full turn... I think)
Refill with 134a compatible Refrigerant oil that your COMPRESSOR IS DESIGNED FOR! Use the proper amount!

Now somethings you may not know. Each can of 134a is not 1lb... its 13 oz. And on top of that it's also got close to 2 oz. in oil... so that's 11oz in the can.
You do know that each can can be anywhere between $9-16 and that ain't cheap.
So you've been told to fill with the proper amount of oil yet each can you add will add 2 more oz. of oil.. Why did I say that?

Because of what you DON'T know R134a comes in a much cheaper supply and it's DRY.

Here's the MSDS of the off the shelf can of Johnsen's R134a cans.
http://www.johnsens.com/uploads/files/6312.pdf
this says it contains 1,1,1,2 TetraFluoroethane ... And yes that's what R134a is.

Now let's do some searching.
Goto wally world and read the can of computer duster spray. 1,1,1,2 TetraFluoroethane...... Hmmmm R134a!!! and it's cheaper....

Now how do you get it in the systerm... Easy. A CAN TAP! One that punctures the side of the can, just be sure to do it near an end so it's supported a little more.

This is very interesting. I always thought that stuff smelled and acted like refrigerant when using it. I'm definately gonna look into this, I already have the tool to use it. Here's some pics of the reguired tool. Mine is part of a complete guage set, which wouldn't really be needed (but is prefered). There are cheaper "can puncturers" for this application. Thanks DIY_Stu!

[This message has been edited by 1fatcat (edited 07-09-2011).]

By "dry" , I believe he means that it's oil-free.

quote Originally posted by DJErikd: By "dry" , I believe he means that it's oil-free.

Ahh, that makes more sence.

That is true I found the exact can you are using today after the post and it's dry too. With that tap you may need to make a spacer to take up some of the area. the duster can is the size of spray paint. a little smaller than the refrig cans.

Thats awesome, it explains why the duster spray was climbing in price.
I always thought the duster spray was a rip off, now it looks cheap. (for AC, not dusting)

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"DRIVE IT LIKE A FIERO"
'84 Fiero, engine to be determined
'87Blue GT 3.4L Swap Completed!!!!!!!! Boosted!!!!!!!
^^^^ Now in the Construction Zone^^^^
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I went to walmart and looked at the Dust-Off Duster, the can I looked at isn't the same as r134.

The duster can label read 1,1 difluoroethane (r152)

The real r134 can read 1,1,1,2 tetrafluoroethane

Use LP gas and be done with it.

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Turbo 3800 E85 5spd spec5
11.53@126.7

quote Originally posted by Justinbart: Use LP gas and be done with it.

Yea, done with the car. when Fiero AC lines bust/leak it is usally pointed right at the exhaust manifold
seen many blow all the coolent onto the manifold, you use LP and the car will burn to the ground at the first leak.
BAD BAD BAD idea

quote Originally posted by sardonyx247: Yea, done with the car. when Fiero AC lines bust/leak it is usally pointed right at the exhaust manifold seen many blow all the coolent onto the manifold, you use LP and the car will burn to the ground at the first leak. BAD BAD BAD idea

Fuel lines are sometimes close to the exhaust and are definitely close to a hot engine. One leak and it burns to the ground also. Been there, done that.

quote Originally posted by sportcoupe: Fuel lines are sometimes close to the exhaust and are definitely close to a hot engine. One leak and it burns to the ground also. Been there, done that.

My car never did burn to the ground. Funny that.

quote Originally posted by sportcoupe: Fuel lines are sometimes close to the exhaust and are definitely close to a hot engine. One leak and it burns to the ground also. Been there, done that.

quote Originally posted by sardonyx247: Yea, done with the car. when Fiero AC lines bust/leak it is usally pointed right at the exhaust manifold seen many blow all the coolent onto the manifold, you use LP and the car will burn to the ground at the first leak. BAD BAD BAD idea

The oil is quite flammable and it won't matter if R-12, R-134 or propane is the refridgerant. If the line blows toward an exhaust manifold, the oil is likely going up in flames.

Now as far a propane, I personally wouldn't do it but I've seen it done several times. Even on a system with a slight leak and there weren't any problems.

[This message has been edited by Joe 1320 (edited 07-11-2011).]

quote Originally posted by sportcoupe: Fuel lines are sometimes close to the exhaust and are definitely close to a hot engine. One leak and it burns to the ground also. Been there, done that.

Yeah except fuel lines were designed to contain a flammable liquid, a/c lines were not.

R134a works fine, why mess with propane and risk blowing yourself up?

r134a liquid is extremely flammable......as far as i knew..

quote Originally posted by dobey: My car never did burn to the ground. Funny that.

Using that logic you might as well go with the propane..........

quote Originally posted by sportcoupe: Using that logic you might as well go with the propane..........

Well, about 4.5 years ago, it had a fuel leak at the filter, which is right next to the cat, and didn't catch fire. Then a couple years ago, the feed line connection for the stainless braided lines that I had installed after the first leak, loosened up and started spraying fuel out the top. And it never caught fire.

I'm not saying you should put LPG in your AC system; but a blanket statement about "if you have a fuel leak, your car WILL BURN" is also not true. I was merely providing a counter-example to your statement that it will definitely result in fire.

Now, as far as R134a goes, it's not generally flammable in the conditions that would result from normal accidents involving a car accident. Here's a video showing a lack of huge balls of flame, from an R134 system spraying directly onto a 970 degrees Celsius heat source:



Unless your AC system is overloaded with oil and other combustibles, the chance for ignition is minimal, at very high temperatures, and probably won't spread.

There's a video that was posted on here a few months ago showing a test they did "across the pond" by putting one of those flammable refrigerants into a car and then they simulated an evaporator core leak inside the car. The guy in the car lit a cigarette after the concentration built up enough and it blew the windows out and put him (and some other people standing around the car) in the hospital with cuts and burns. That's why no auto manufacturer uses a flammable refrigerant in their HVAC systems and that's also one of the reasons why I wouldn't use them either. Not to mention the fact that once you put propane or any other "replacement for R12 or R134a" refrigerant into your car, NO A/C shop will ever touch it again because they don't want their equipment contaminated.

It never ceases to amaze me how many people step over a dollar to pick up a dime on this forum. If you have a properly working (and sealed) A/C system, the refrigerant won't leak out for years, if ever; and there will be no need to keep adding refrigerant to it. If your system has a leak, the first thing to leak out is usually the oil (that's because the oil is what forms the barrier between the refrigerant and seals to keep the refrigerant in the system). And once the oil is gone, your compressor won't last long before destroying itself anyway.

So I don't understand why anybody would want to go cheap here and keep "adding cans" to their car every year instead of FIXING the leak so they only need to charge it once and be done. R134a if purchased at $15 a can (that's about as expensive as I've seen it) still isn't that expensive if you only have to do it once. Fix your leaks and you won't have to worry about the expense of R134a but once.

By the way, I bought a 30lb cylinder of R134a at Sam's Club for $200. That works out to $6.67 / lb.

-ryan

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OVERKILL IS UNDERRATED

Custom GM OBD1 & OBD2 Tuning | Engine Conversions & more | www.gmtuners.com

[This message has been edited by Darth Fiero (edited 07-11-2011).]

I was going to respond to the misinformation concerning propane as a refrigerant and the "explosive hazrd" it would create, but I decided instead to ask if any one had ever heard of the terms 'upper explosive limit' and 'lower explosive limit'.

Look the terms up, eddykate yoselfs, and move on with your misconceptions.

Edit to add - Ryan is absolutely right - fix your leaks, use the right stuff. But, will propane in your A/C blow up your car? Look up the terms and do the math.

[This message has been edited by olejoedad (edited 07-11-2011).]

Found the thread with the video in it: https://www.fiero.nl/forum/F...HTML/108969.html#p14

Looks like it only took one can of the stuff to give a high enough concentration for the explosion to occur. Is this REALLY what you want to use in your car when we know evaporator cores can and do leak and rupture?

No thanks.

Other things to consider, with propane, there are a TON of unknowns. Collisions, mechanical failures, surrounding temperatures near the leaking gas, ect. Example, what if your compressor went bad and started making metal-on-metal contact inside? How hot will the parts get? I've seen many compressors lock tite due to friction. The parts get so hot that they glow red, very much like welding.

Not worth the risk to me or to anyone I know. R134a is still cheap enough. At 20 a can (most systems take 2-3 cans (w-w/o rear a/c) your talking about 40-60 in refrigerant...and thats high balling it!

How much would the propane cost? How you gonna get it from the bottle to the car? By the time you figure the propane cost and tools to move it from the bottle to the car, you could have just bought the 134.

Minor note:

If a person were to use propane or similar for AC work and were to have an accident where there was a resulting fire and/or explosion due to the propane, the person's insurance company will reject all related claims and say, so sorry, too bad, no coverage here, move along. Just a minor factor to be aware of.

So how would the insurance company know the fire was from propane, where the propane came from, or who put it in there?

[This message has been edited by phonedawgz (edited 07-11-2011).]

quote Originally posted by JazzMan: Minor note: If a person were to use propane or similar for AC work and were to have an accident where there was a resulting fire and/or explosion due to the propane, the person's insurance company will reject all related claims and say, so sorry, too bad, no coverage here, move along. Just a minor factor to be aware of.

Also, you'd probably be set up for a pretty hefty fine, and/or federal prison time.

So blame the fire on it on being a Fiero. Everyone will believe that.

Propane mixed with refrigerant oil when released under pressure is highly explosive. R-134a mixed with oil is somewhat flammable but not an explosion threat. Gasoline lines that are under 40 psi of pressure are no where near as dangerous as propane concentrated and being circulated at high pressures which can reach 150 to 200 psi in an auto A/C system. Gasoline is contained in fuel injection hoses. Propane in an A/C system has to be contained by O rings all over the lines AND at a compressor seal that retains the gas around the rotating compressor shaft. This makes refrigerant more likely to leak out and if it fills the pasenger compartment and ignited, you'll be lucky if you come out medium rare instead of well done.
Want to save money on R-134a? Buy it at the discount warehouses in winter. During summer months you'll always pay through the nose becuase they know that they gotcha by the balls.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite.
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quote Originally posted by Dennis LaGrua: Want to save money on R-134a? Buy it at the discount warehouses in winter. During summer months you'll always pay through the nose becuase they know that they gotcha by the balls.

Indeed. And as Darth said above, fix your busted AC system. Having to buy new refrigerant all the time is no way to save money.

Hydrocarbon refrigerants have been legal for automotive A/C use in Canada and Australia for many years. They are also legal to use in the U.S. (to replace R-134a) in more than half the States. I wonder if there are any statistics on the number of vehicle fires caused by those?

Also, hydrocarbons are now used in many European refrigerators so there may be statistics on that use also.

If there is increased risk from using hydrocarbon refrigerants, there should be real world evidence by now. Maybe there is?

quote Originally posted by spark1: Hydrocarbon refrigerants have been legal for automotive A/C use in Canada and Australia for many years. They are also legal to use in the U.S. (to replace R-134a) in more than half the States. I wonder if there are any statistics on the number of vehicle fires caused by those? Also, hydrocarbons are now used in many European refrigerators so there may be statistics on that use also. If there is increased risk from using hydrocarbon refrigerants, there should be real world evidence by now. Maybe there is?

Not quite;

http://www.epa.gov/ozone/sn...nts/hc12alng.html#q2

http://www.epa.gov/ozone/sn...ts/hc12alng.html#q16

quote Originally posted by Dennis LaGrua: Want to save money on R-134a? Buy it at the discount warehouses in winter. During summer months you'll always pay through the nose becuase they know that they gotcha by the balls.

Did you forget the TITLE and first post of this thread?

IMO; if you want r134 then buy r134. If you buy computer duster spray hoping for cheap r134 you will probably not be getting r134 unless you're real careful and read the labels. Not all duster sprays are the same.

Well that certainly explains why my hand freezes when I dust my keyboard

I've done some (albeit not a complete) study of "gas dusters". While some do use R134a most do not. The majority of manufacture use some other, less regulated, refrigerant. The major issue with using those that do use R134a as a cheap replacement for auto AC use is that it is not the only thing inside the can. A 12 oz can of a duster will not have 12 oz of 134 in it. How much will very but you have to remember that it is there as a propellent not as the main product. In the products I looked at over half the can was air. If you went to the trouble of removing only the liquid 134 I am sure that your total cost would be more the buying the real thing.

The thing I tell my customers is that you don't need to buy the cans that say they contain some type of "super cool" or "arctic ice". Your system will only cool so far and that's it. Also don't buy those that contain leak stoppers, oils, dyes or other items unless you need them. And then check to see if you can buy what you need separately because you can normally buy it cheaper that way and get the correct amount you need.

quote Originally posted by dobey: Not quite; http://www.epa.gov/ozone/sn...nts/hc12alng.html#q2 http://www.epa.gov/ozone/sn...ts/hc12alng.html#q16

I don't see where what I said conflicts with the EPA statement which reads:

quote Is it legal to replace HFC-134a in a motor vehicle with hydrocarbon refrigerants such as DURACOOL 12a® and HC-12a®? In certain circumstances, the replacement of HFC-134a in a motor vehicle with hydrocarbon refrigerants might be permitted. At a minimum, in order to avoid violating the Clean Air Act, the motor vehicle A/C system must have either been originally designed for use with HFC-134a refrigerant, or must have been previously retrofitted from CFC-12 to HFC-134a refrigerant, AND no sham retrofit must have occurred to convert the system to the hydrocarbon refrigerant. In order to avoid violating other laws, the replacement of the refrigerant must not violate any state or local prohibition on the use of flammable refrigerants in motor vehicle A/C systems. The following 19 states ban the use of flammable refrigerants such as HC-12a® and DURACOOL 12a® in motor vehicle air conditioning, regardless of the original refrigerant: Arkansas, Arizona, Connecticut, Florida, Idaho, Indiana, Iowa, Kansas, Louisiana, Maryland, Nebraska, North Dakota, Oklahoma, Texas, Utah, Virginia, Wisconsin, Washington, and the District of Columbia. EPA and hotline staff will not, based solely on facts given in a phone call or letter, determine the legality under the SNAP program of using a hydrocarbon refrigerant in a motor vehicle retrofitted to use HFC-134a, because the determination depends on many factors, including the nature of the retrofit from CFC-12 to HFC-134a, the reason for the retrofit, and the exact procedure and timing involved. If you plan to change a car from HFC-134a to a hydrocarbon refrigerant such as HC-12a® and DURACOOL 12a®, you should consider that auto manufacturers have stated that changing the refrigerant in new vehicles designed for use with HFC-134a will void the warranty and may damage the system. If the air conditioner on a new car or truck is not working, consult a qualified mechanic or your dealer.

The only part of the EPA statement I disagree with is that I don't consider the District of Columbia to be a State. Hydrocarbons are banned in 18 States which is still less than half of 50.

[This message has been edited by spark1 (edited 07-14-2011).]

quote Originally posted by 1fatcat: How hot will the parts get? I've seen many compressors lock tite due to friction. The parts get so hot that they glow red, very much like welding.

Why is fire such a hard concept to grasp? Why doesn't a propane torch not explode when you light it? Its not magic, there is no oxygen in the tank therefore the propane in the tank can't ignite. There is no way you compressor locking up could cause the Propane to ignite unless there was a fuel air mixture in you ac lines.

quote Originally posted by ARKaiser: I've done some (albeit not a complete) study of "gas dusters". While some do use R134a most do not. The majority of manufacture use some other, less regulated, refrigerant. The major issue with using those that do use R134a as a cheap replacement for auto AC use is that it is not the only thing inside the can. A 12 oz can of a duster will not have 12 oz of 134 in it. How much will very but you have to remember that it is there as a propellent not as the main product. In the products I looked at over half the can was air. If you went to the trouble of removing only the liquid 134 I am sure that your total cost would be more the buying the real thing. The thing I tell my customers is that you don't need to buy the cans that say they contain some type of "super cool" or "arctic ice". Your system will only cool so far and that's it. Also don't buy those that contain leak stoppers, oils, dyes or other items unless you need them. And then check to see if you can buy what you need separately because you can normally buy it cheaper that way and get the correct amount you need.

R-12 was once the propellent used in Albuterol inhalers used to treat asthma symptoms. Those were converted to R-134a a few years ago too. The only difference now is that the R-134a types come with a dose counter and are sealed in a foil pouch along with a desiccant. Oh, and the price doubled.

quote Originally posted by spark1: The only part of the EPA statement I disagree with is that I don't consider the District of Columbia to be a State. Hydrocarbons are banned in 18 States which is still less than half of 50.

They are only legal in some cases in those states, and only when it is not in violation of the Federal law and Clean Air Act.

But it's a dumb idea to do it anyway, even if it does fall under a case where it is legal.

quote Originally posted by jmbishop: Why is fire such a hard concept to grasp? Why doesn't a propane torch not explode when you light it? Its not magic, there is no oxygen in the tank therefore the propane in the tank can't ignite. There is no way you compressor locking up could cause the Propane to ignite unless there was a fuel air mixture in you ac lines.

As I said earlier, there are a TON of unknowns. I've seen compressors lock so hard that they split the case open. Would that be enough oxygen?