Automotive Air Conditioning - R12 and R134a: How do they affect us?

by Ellsworth Chou

The refrigerant in your pre-1990 automobile was banned from manufacture in the U.S. in the mid-1990s. The remaining stock of this chloroflourocarbon R-12 has been depleting ever since. Strict Federal mandates and tariffs discourage their continued use in older vehicles. What are the issues and how will they affect the American consumer? I did some research for my own edification, and here are some of my observations.

(This page was extracted from an emailing that I sent to friends in August of 1994. In some ways, it's more timely, as the use of chloroflourocarbons (CFCs) has reached an even more critical state. On the other hand, I haven't really kept up with the topic, so some of this may no longer be relevant. Hope it's helpful nonetheless. -Ellsworth Chou)

"NO MORE R-12?"

This is a topic that'll affect all of us eventually. Globally, if not personally. I'm hoping this note helps in both ways.

Burbank, California:

• Over the last couple of years, the air conditioning system in my car has slowly lost refrigerant. This summer, it finally lost enough Freon to quit working altogether. We've put off servicing the car, not wanting to spend the significant cash (3 years ago, it cost around $300 to replace the hoses on my wife's 1987 Shelby Charger and recharge the system).
• For those of you who haven't noticed, automobile refrigerants have gone through a radical change over the last several years. First, in the late 80's, the Feds imposed tariffs on the purchase of Freon R-12, which they claimed was an environmental impact penalty of sorts. Funds collected from this tariff were to go to research or activities to correct or reduce ozone layer damage caused by CFCs (chloroflourocarbons). The tariffs raised the price of a small can (16 oz.) of R-12 from around $1.50 to almost $15! That, it turns out, was just the beginning. In an unusual display of bureaucratic efficiency, businesses servicing automobile air conditioning systems were soon required to manage the waste Freon with expensive reclamation systems. In 1990, President George Bush OKed a federal mandate to require automobile manufacturers to produce alternatives to CFC-based refrigeration systems. By 1995, CFCs were to be all but gone from new vehicles.
• Out of desperation (and heat prostration), I went to [the local do-it-yourself auto parts retail outlet] and looked to see how much Freon was and what kind of leak-seal stuff there was. I felt kinda guilty about it - this is just the activity that the Feds are trying to prevent. There's no surer way to release CFCs into the atmosphere than adding some to a vehicle which is leaking. Well, it turns out the Feds have that covered. There was no R-12 Freon in the store. Well, that's not exactly true. There might've been some in the store, but ONLY by the twenty pound can, and ONLY to certified air conditioning service businesses, and for ONLY around $270 a can. There was plenty of R-134a.
• What is R-134a, you ask? I'd noticed for several years that auto manufacturers had started building cars with air conditioning systems using this replacement for the "ozone-depleting" R-12 Freon. R-134a is a hydroflourocarbon (HFC), and is considered a "safer" refrigerate than the CFC R-12. One source I've read said that R-134a is "95% less damaging" to the ozone layer than R-12.
  • Problem #1: R-134a is significantly less efficient as a refrigerant than R-12. Its higher "latent heat of vaporization" means that something like 40% more of the energy expended in compressing it goes off as waste heat. As a result, existing air conditioning hardware can't effectively use it. I'd guess that if you did run R-134a in an old R-12 system, you'd barely see any cooling on really hot days. Factory R-134a A/C systems have more powerful compressors and more robust condensers, evaporators and driers. This means hundreds of dollars in system conversion, if the conversions are available (I'd noticed that R-134a systems added some $400 to new early 90's Volvos - one of the first manufacturers to produce). But there's more: I read several documents that said that you should never mix the coolants or the hardware between the R-12 and R-134a systems, but nothing explained why. When I finally discovered the difference in system pressures, it was obvious about some of the questions. In fact, service fittings on R-134a system are intentionally designed to be incompatible with R-12 (It'd be bad to have service gauges and reclamation machines exploding). But one thing kept nagging me - why forbid the use of R-134a refrigerant in R-12 systems? I mean, if I want an inefficient A/C system, that's my problem, right? Uh, nope. Turns out there's something else:
  • Problem #2: HFCs have a bad habit of diffusing right through the hoses that are designed to contain CFCs. They'll only cool about 50% as well, and cause 5% of the ozone damage, but they'll leak out of your car in a couple of days. R-134a system use special hoses with Nylon-cladding on the inside to prevent HFC diffusion. (It's a good thing that not all of the copies of Haynes' "Air Conditioning and Heating Systems" at Pep Boys were still sealed in plastic.) Huh. And, I suppose, those Nylon-clad hoses have fittings which aren't compatible with R-12 systems.
• So the Good News is that Uncle Sam has done something in Short Time and We and Our Children and Our Children's Children will benefit from it. The Bad News is that if you own a car that was produced after 1990 or one of the last holdouts to produce new CFC A/C systems, you're in an awkward (read: expensive) position. If you were the do-it-yourself sort that added you own Freon - that is apparently at an end (let me know if your state has taken the same actions). Now, you'll apparently have to get all your A/C work done at a Certified Air Conditioning Service Center and pay: whatever tariffs the Gummint has decided to put on the purchase of R-12; the penalties that the Certified Service Center has to pay for handling and disposingof R-12 (which that tariff on the purchasewas probably supposed to cover); overhead for the exotic-looking Freon Reclamation Equipment that every service station is now required to have; and God Knows whatever the Certified Service Center wants to surgically remove from your wallet for Parts and Labor because Ain't Nobody Else Gonna Be Allowed To Get Or Work On This Stuff. The point is, the only way that the Powers That Be have of insuring that the remaining (oh, coupla hundred million) R-12 cars don't just leak that stuff out into the atmosphere is to prevent bozos (like me) from "fixing" air conditioning systems themselves.
• Has anybody else run into this yet? What kinda prices are people in your part of the country quoting for R-12 service? Has anybody gotten a quote on an R-134a CONVERSION? (Yeah, right.) I guess if a conversion is $800 and a servicing is $400, I might consider the conversion (we expect to keep our collectible cars indefinitely). I suspect the conversion will actually run much higher. Hope this opened some eyes and at least saved someone from Future Service Quote Shock. Let me know what you turn up. If we can gather enough reliable data, we'll contribute this to the electronic public. Happy (and Cool) Motoring!

August 8, 1994 "R-12 UPDATE"

• Well, out of curiosity (and desperation - or perhaps perspiration), I went to some "while you wait" service place with a coupon for a $19.95 ($10 off) auto air conditioning service. The coupon said that the rate included leak detection, gasket and belt inspection, and system evacuation and recharging, Freon NOT included (turns out they charge $18.95/pound for R-12). I figured I'd see what they could do about the refrigerant loss. The answer: nada. Nuttin'. After starting the car and turning on the air conditioning, the mechanic informed me that there was "no Freon in the system. He pumps some compressed air into the system and listens around the engine compartment (engine off). He then tells me that the leak is "too small to fix. He tells me I need to go to an air conditioning repair place to get it fixed. Oh. Gee. Never thought of that. So this implies that these people are charging people MONEY to take out their old Freon and put in new Freon. If you've lost Freon, they can't help.
• My question is, why would you want to change your Freon? I was under the impression that Freon was pretty much inert in your A/C system. On the plus side, this mechanic wouldn't recharge my system because it would just leak out and "pollute the air." Well, at least he knows there's something wrong with letting this stuff into the atmosphere. I'd hope the EPA threatens to secretly send out "customers" to insure that auto shops aren't just contributing to our CFC problems. On this first mechanic's recommendation, I visit an auto A/C repair shop in Burbank. They're busy, and it's in the mid 90s in L.A. A mechanic takes a look under the hood and reports that "these Chrysler hoses" are known to have had problems. He points out the thin film of oil on the surface of the hoses. I'd noticed the oil for years, but never imagined what the mechanism was that got the oil on the surface of the hoses. I figured it was leaking out somewhere and flowing over the surface. Turns out the R-12 and refrigerant oil migrate through the hose wall. You may recall that was the problem with R-134a and hoses intended for R-12. But you'd think that R-12 hoses could contain R-12. I'm not sure if the "Chrysler hoses problem" was real, but hose replacement was the solution to the refrigerant loss on my wife's car.
• Anyway, I ask for an estimate for hose replacement. The mechanic says it'll be $300 for "high-side" (of the compressor) hoses and as much as $375 if the "low-side" are bad - the rates include evacuation and recharging. This is around 25% more than what we paid for Joni's A/C hose replacement three years ago at a different shop, so it's reasonable - if expensive. Out of curiosity, I asked about R-134a conversion. He quoted at least $600, which didn't sound bad. For the conversion, the "expansion block," or "expansion chamber" is replaced; R-134a compatible hoses are installed; and the system is flushed of the original lubricants. He said it could be as much as $200 more if the compressor had to be replaced - apparently many original R-12 compressors can handle the higher pressures. But he didn't imply that the other major components: evaporator, condenser and drier, required replacing. Even at $800, that's far better than the $1800 "plus change" that someone I know had to pay to convert one of their Ford Aerostars, which did have a bad condenser. The mechanic at the auto air place quoted R-12 at "almost $20 a pound" and "almost $100" to recharge most cars. He said that they expected to have R-12 "until the year 2000", so suggested I base the decision to convert on how long we'd keep a car.
• A friend told me last week that she remembered reading some time ago that R-12 would no longer be available in North Carolina after a certain date. She's not sure if the date has passed or not. The day after (8/3/94) she wrote me:
  "in the morning edition of the [local newspaper] there was an advertisement for Freon R-12. It was an Auto-Zone ad and the price for a 12 oz. can is $6.95--they also advertised the bigger cans and I believe the next price up was $169 or $179 per big can. I was mighty surprised because as I told you in my note yesterday, my understanding was that no more Freon R-12 would be sold in NC to the average consumer. In closing, an article from a recent issue of AAA of the Carolinas monthly member publication said that the cost of an air conditioning recharge had increased to over $100. They advised only buying cars designed for HFC-134a, and making sure that any repair shop converting a vehicle to 134a guarantee it in writing for at least 90 days or 4,000 miles.

So KEEP COOL out there.

The information contained in this article is strictly from [my flawed and deteriorating] memory, so Do Your Own Research. 

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