R12 or R134 ?

Did they change the hose fittings and all the seals in the system before they put in the R-134?

It is my understanding that R-134 will leak out of an R-12 system without these changes.

 

I know the oils are not compatable between the two, but if they did a good vac hopefully that got it all. (I'm not what process is used to "flush" the systems).

Any possiblity to have them re-vac the system and install the R12 again?

 

It is no longer SOP to disassemble the system to change o-rings and seals for the R-134 conversion.

OTOH, it IS SOP to remove and drain the compressor of old oil, add new R-134-compatible oil, change the drier and change the fittings so no one who might service it later makes a mistake and contaminates the system.

-Peter (prefer R-12 every day of the week)

 

Frank,

I understand you replaced the receiver/drier not long ago. Ron Rieneke suggested doing this to my Boxer since it is apart in his shop. he mentioned you had done this.

Did your problems start when the receiver/drier were replaced?

Drew

 

It will never cool as well as it did with R12. I have been told by many mechanics that the system runs at diiferent temps with 134 and the condensor and other components were not designed for this.I would go back to R12 for sure.

 

I JUST went thru this with two of my cars. STAY WITH R12 if at all possible!!!.
You cannot simply vacuum it out and put in 134 along with a new dryer. It is a bigger molecule and an old R12 system's condenser is really not big enough to get enough of it in. If you do convert - ALL the old oil needs to be removed which means pulling and draining the compressor, etc.
I lived with 134 for a couple of months but I just could not deal with it anymore. I did a complete conversion BACK to R12. They now are blowing COLD again.

It is a bit more $$$ but if you don't have a leak, so what? You don't change it like you do crankcase oil.

 

Tommy, How hard was it to get all of the 134 out? I changed mine to 134 about a year ago when I had to repair the system anyway and replaced most of the o-rings, but nevertheless it has gradually leaked out. I am assuming it has leaked out as the AC performance decreased gradually. Now I am in the position of having to either recharge with 134 or go back to the R12. I live in Texas and AC is mandatory. It seemed to do okay with the 134 last year, but it did not cool as well as it did with the R12. Adding 134 is the easiest thing to do, so I might try it again and see how it does and if I am not happy will go back to the R12. My decision however is somewhat dependent on how much it costs to go back to the R12. It looks like I would need at least a new drier which may cost about $282.00. However, I have no idea how much it would cost to drain the compressor properly. I don't know how easy or difficult job it would be in my 512TR for an experienced AC mechanic.

 

Lolaman is 100% right. The main thing is that the oil used for R12 is not compatible with R134, so the oil in the compressor needs to be changed over, the system pumped to a vacuum, then refilled with R134.

If the R134 is done right, the system will be pretty close to R12, but not quite as good. The difference is something like 8% worse. Don't quote me on the exact number. Up here in New England, we have some pretty hot/humid days in the summer (90+ degrees) and the R134 barely keeps up with it. The 308 is tolerable, though not frigid the way I would like it. I cannot compare to how it was with R12 because I bought the car with the AC nonfunctional and Verell & I converted it to R134 when we went through it.

R134 is pretty cheap though, and topping it off will only cost like $10 if you have a set of guages. That makes it worth it over R12 for me.

Birdman

 

It actually wasn't my Ferrari, It was 2 of my Sciroccos and it was still a bit of work. At least everything is where you can reach it on those cars.

We pulled the compressor and emptied it (as best you can) and replaced the expansion valve and dryer. Then we blew lines out and pulled a vacuum for about a day. That's really all you can do short of replacing everything. That is why I never saw it as cost effective to go 134. By the time you spend what you have to to do a complete change-over (so it will work as best it can), you could have just paid for the R12 and had a colder a/c. The 134 conversion really only pays for itself if you have to keep adding the 134 chemical. That's where the savings comes in and if you find yourself buying 134 at a rate that it becomes "worth it" you have another problem entirely which is totally unrelated to what freon is in your system.

 

R134 does not absorb heat as well as R12 and is not very efficient as a retro fit on older A/C systems. I experienced this once with a 700 series BMW.

Newer systems today designed with R134 have larger evaporators and condensors to equal that which was used on R12 systems.

Sure, it's environmentally friendly, but you'd be best off to stay with R12 if that is what was originally in your system.

 

The price for R-12 is a little more tolerable than it used to be. I have no difficulty buying R-12 with my certification in 30 lb tanks for the shop. We pay between $19-$22/lb now. At one time I think we were paying nearly twice that. I don't normally convert an R-12 car to R-134 unless there is major component replacement going on, namely the compressor, which requires a replacement of the receiver/drier anyway. I do not, as a matter of course, replace the o-rings or the expansion valve, but I do flush the system and change the oil as I replace the compressor.

If at all possible, I keep the R-12. GCalo is correct, it is an efficiency issue. Larger condensors and evaporators are required for R-134 to match the thermal transfer efficiency of the equivalent R-12 system.

It get's hot down here!

-Peter (nice and cool in my R-12 Mondial t Coupe)

 

Any conversion I have done with vehicles in the past with R12 to 134 has caused compressor failure eventually. The oils are not compatable between the 2 and you never can get all the old R12 oil out of the compressor.

they should have replaced the drier as well as its contaminated with old oil.

I'd keep R12 and replace the drier again, you can also go to Freeze 12 which is compatible with R12 and its oil and its cheaper than R12.

A vac test should show if the compressor is leaking while the car is running.

 

My 86 Porsche 944 Turbo and 89 Geo Metro have been converted for 2 years. If the humidity is high the Metro puts out snow flakes on a 99 degree
day. I had the air removed from my 308 GTSi as I drive with the top off 9
months a year.

stephen

 

I have found that GM makes the best A/C by far. My GM work van A/C stuns me even on the hotest days.

So, I am not surprised to hear about your Metro even with the R134.

I have a few friends who wanted to be environmentally conscious with perfectly functioning R12 systems and coverted to R134.

What a mistake.

Keep your R12 and forget the environment! If it's working it's not harming the environment!

 

I know this will set a few people off, but here goes.

One of the tricks I learned from an older Engineer was that R-290 (Propane) is used a lot in Europe as a replacement refrigerant for R-12... It has a lower boiling point than R-12 so it works about 25% better, is compatible with the seals and oils for R-12, and is a heck of a lot cheaper. He charged it into his Cadillac and a walk-in refrigerator when they ran low on R-12. The Caddy blows snow out of the vents in high humidity, and the reefer went 20 degrees cooler at the same settings as for Freon. He had to re-mark the temperature gauge dial. All it takes is a creative set of fittings, and you charge it in to the same pressures as you would Freon. He charged it in along WITH the Freon already in the system, and both systems have ran just fine for the last 9 years.

In the US this is considered illegal by the certification agency for refrigeration techs to use Propane, but they won't tell you why it's banned. Yes it is flamable, but then so is gasoline and it's piped around under pressure in your car's engine compartment already. I don't buy the "flammable" argument. R-134 with it's oil entrained is flammable too.

I use AutoFrost in mine in place of R-12. AutoFrost is a mixture of refrigerants and works just fine in my Mondial, but it takes a license to buy it. Propane is one of the fluids in the mix. I need to replace the dryer to get the excess moisture out of my system, so I'll be recharging it here again pretty soon.

Wasn't it convenient how R-134 came out at the same time R-12 was banned in the US... both patents held by Dupont? Hmmmmmm.

Thor
www.JavelinArt.com

 

Those guys jacked your system. Maybe they can pay you the thoudands of dollars to make it right again. Non one should change the system w/o consulting you. r12 cools better tahn 134 but new 134 designed systems are good. r12 is still available and anyone can take the test and be r12 licensed. I do have a new 30lb can of r12 if anyone with a valid license needs one. There are very specific ways to change r12 to 134 and it does not sound like these guys did it.

 

EXACTLY

 

FYI, I work with refrig in none automotive applications (wine cellar) and my experience with retrofit is similar. New R134 systems are bulletproof and efficient. Retrofit R12 to R134 is always problematic, and R12 substitutes are not much better. R12 substitute blends (hotshot,etc.) work well at first, but will seperate, and topping off a system is not possible, a full evacuation and recharge is needed. Make sure your shop is using new R12 (best, but $$$$),
reclaimed R12 (not as good, but ok), or if they are using "drop in" blends find out, and be ready for the issues that come along.
My .02

-L

 

I like that propane idea! What a gas!

I could cook hot dogs while cooling my tootsies! I'd love to give that a try except all my current cars now use R134.

I used to but R12 in small cans 6 at a time for $.99/can! Can you believe it!

I was king for a while with friends keeping their A/C systems up to date in the Boston area during those humid summers.

I still like the propane idea, however.

 

I have heard of propane before but their were issues with it I can't recall but if it works that would be great, you can get A/C charging adaptors and hoses at NAPA.

Harbor Freight sells a vacuum device for A/C systems that works off a air compressor as well to evacuate your system so a DIY propane charge is doable.

 

another FYI,
Some of the blends use propane or other FLAMMABLE COMPRESSED GAS !!
I think we don't need additional ways to create F-car engine compartment fires.

Although.....
http://www.ferrarichat.com/forum/showthread.php?t=107530

 

If you ever do charge with propane a a/c service center will not want to service it as the machines can identify flammble gases with hydrocarbons such as propane.

Back to the original post the Viton seals in a/c systems in Euro cars are not compatible with 134a including the compressor seals, so it will eat them away.