Joined: Sat 10-18-2003 10:26PM Posts: 2954 Location: Stone's throw from Garden of the Gods, Colorado Springs
Source: Fidelity
I should clarify. It's an easy DIY project. But for a Freon (R-12) system, it's just not easy to do --right--. By right I mean, legally, cheaply, properly--but you can only pick 2. You have to keep in mind these considerations.
Legality--It's illegal to vent R-12 into the atmosphere, it being regulated as a CFC and all. It's also illegal to purchase R-12 or to attempt to recover R-12 from a cooling system unless you're an HVAC tech who's licensed to handle R-12.
Proper installation--An R-12 system should ideally be filled only with R-12 (Freon), in order to keep the safety of the compressor's seals in mind. Alternately, you can complete an R-134a retrofit by purging the system of R-12 and replacing the system's fill fittings with 134a fittings. You can then fill it with the new, CFC-free R-134a refrigerant if you also add a special oil that's designed to protect the seals in the R-12 system. This is a little riskier for the equpipment, but the oil takes care of most of the compatibility problems with the retrofit.
Cost--An 8-oz can of R-12 can go for as much as $150, not to mention the cost of the licensing to handle the stuff. Comparatively, a 12-oz can of R-134a can be had for $1.96 down at the Wal-Mart. Functionally, they're nearly equivalent. Thermodynamic properties are different, but similar enough for the two to function effectively together.
Given all of this...what I have done for older vehicles I've owned in the past that have used R-12 refrigerant is the following.
-Purchase an R-134a retrofit kit at Wal-Mart for around $20. This will include the new fill nipples, 3--16 oz cans of refrigerant, 1--8 oz can of oil, a metering and dispensing device, and a Retrofit underhood sticker.
-Find the low-pressure side of the system. The Mason/Dixon line here is the A/C compressor, which will (obviously) be somewhere in the drive line. In a properly working A/C system, the low-pressure side will be the COLD side of the system. It's the side with the accumulator (the big silver cylinder looking thing). Trace the tubing around until you get to a nipple--that's the fill nipple.
-WITHOUT venting any refrigerant, (Or you know what? It doesn't honestly matter. Kill some trees. I don't like wasting the good refrigerant but you know.) put on the new retrofit nipple (it just screws on) and check the fill pressure. If it's good, then you have a different AC problem entirely. Likely it won't be.
-If you need to fill, run the engine and the air conditioner on MAX, these will need to run for the entire process. Connect your fill apparatus to the fill nipple, and attach the oil can, and install it into the system. It'll take some time, a few minutes.
-Then install the cans of 134a. You'll need one or two cans.
If your system doesn't have a vicious leak (in which case the system won't hold pressure and you'll be able to see all your precious refrigerant spray out), and you don't have a compressor problem, or an electrical signal problem preventing the compressor from engaging, then you should be done at this point and you should have nice, cold, AC.
It's worth noting that if your car is a model year 1993 or later (perhaps a few years earlier for some OEMs, notably GM and Ford), then your car ALREADY has R-134a, and recharging by yourself is insanely simple. You ever pumped up a bike tire?
Joined: Tue 08-17-2004 7:24PM Posts: 9 Location: off campus
Source: Off Campus
As an added note, if your a/c pump is cycling on and off in, say, 10 second intervals, or so, it is not building pressure and is likely empty. If it is empty you should pull a vacuum on the system before refilling. The fittings are designed to bleed out any air, but I never have trusted them. If this is what has happened, refilling may work for a while, but a seal is likely leaking. this would mean that you can look forward to refilling occasionally, and more often as time passes on. Depends on if it is cheap enough to you to refill it ever so often, or pay a service tech to "fix" it. My experience with R-12 systems that have been fixed by professionals is that they usually miss a small leak if the UV leak detector does not show up in a convenient location. In this case you can bring your car in many a times, for copious amounts of money, and never really get it fixed. (happened to my mom before i started wrenching on cars )
From my experience, Zane's is untrustworthy and tries to take advantage of their customers who are female and umr students.
I highly recommend American Auto over on 18th Street on the East side of the tracks. You can just walk in and if they arent' too busy then they'll beable to do it then.
_________________ Sometimes the stupidity around you just overwhelms you.
I highly recommend American Auto over on 18th Street on the East side of the tracks. You can just walk in and if they arent' too busy then they'll beable to do it then.
I say never go to American Auto. They do shoddy work and, if it's a relatively simple job, will overcharge you to make up for it. There's a reason that they're hardly ever busy.
Firestone is probably the best in the area, but are also the most expensive.
I like Zane's. They do good work and don't charge an insane amount.
_________________ "If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy." -James Madison
I highly recommend American Auto over on 18th Street on the East side of the tracks. You can just walk in and if they arent' too busy then they'll beable to do it then.
NO. When I was a freshman, I took my Galaxie to them when I didn't have my tools here. They snapped the breaker plate off the distributor, and it barely ran like that. They told me it was bad gas, and charged $200. They couldn't even set points correctly. They didn't even end up fixing what was wrong with it to begin with...I ended up rebuilding the carburetor in my dorm room which was the problem (debris in needle seat). Don't take your car there. ALWAYS keep your tools with you!!
Zanes lied to me and told me it would cost over 1500 to fix my car when a belt connected to the a/c was going bad... yet it only cost 300 at american and my mechanic at home said they did a good job. My mechanic at home i have gone to for over 12 years so i'll trust what he says.
I guess everyone has different experiences with everyone... You can always go up to StL and have a well known chain do it.
_________________ Sometimes the stupidity around you just overwhelms you.
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