R134A or R12 A/C System??

[Cheks_Talon_TSi]

I am about to change the refrigerant/oil of the A/C of my 1G DSM. I have a question before doing this: those my car use the R134a refrigerant??? or the R12??? I don't have the manual of my car, so I can't figure out

Hope someone can help me with this. Thanks in advance

 

[98RedDragon]

you cannot buy r12 anymore, the r134a was made as the replacement, flush it all, then buy a few cans of the 134a, need anymore help, lemme know

 

[Sotarts]

Like he said, r12 is not for sale (not for us common folk, anyway, because the government says it's bad for our atmosphere--that's a whole other subject).

You can go to any auto parts store and pick up a kit of 134a refrigerant, which includes the necessary oil/seal conditioner mix, few cans of refrigerant mixed with lubricating oil and a charging hose (with control valve) with a pressure gauge. Don't just charge your system with few cans of refrigerant.

Your system would have to be flushed out of the old stuff. Government says it's illegal to just vent it into atmosphere and you must go to an authorized auto shop with proper equipment for that purpose. Of course, it will cost you $100+ for that service alone and many places refuse to perform recharge service unless they flush it and check it all for leaks.

 

[Cheks_Talon_TSi]

Thanks, I will buy the R134a. BTW, I saw a bottle of 19 Oz on WalMart that inlcudes: mixed Refrigerant 134A with lubricating oil and seal conditioner. This bottle also include the pressure gauge and the necessary hose. The gauge and hose can be reused for future refills or just to check the system pressure... I saw it for about $19 bucks or something like that, I guess I will go for it...

Thanks for your help!!

Sergio G.

 

[Sotarts]

Go for it.

Buy an extra can or two of refrigerant+oil mix, for future, or in case it's not enough (or sometimes "accidents" happen and some refrigerant might be sprayed out all over the place because of a mistake). Wear gloves--that stuff is super-nasty-greasy-freaky-feeling-and-possibly-more-than-just-toxic.

Recharge port is behind the engine, between firewall and the block, on top of A/C compressor.

 

[TransDSM]

There's a little more involved than just putting R-134A into an R-12 system. The low side and high side valves are different and R-134A eats at the seals used in R-12 system. Also the R-12 needs to be completely cleaned out of the existing system before you add R-134A. The oil in R-12 will not circulate in R-134A Also the dryer needs to be changed for one that is for 134A use. The R-12 one will not take the moisture out of the refridgerant. Also to get the most out of the system it is wise to replace the compressor for one that is designed to work with 134A. Common complaint of people that do the conversion without changing the compressor is the air isn't as cold as it was with R-12. Why are you changing out your R-12? Check your inspection glass and look to see if there is bubbles in it if you are having trouble with the AC. Generally speaking refridgerant doesn't break down. Usually it's a leak that causes loss of pressure which can lead to warmer temps or complete failure.

 

[Sotarts]

I'm sure people will swap out their compressors and dryers just to convert to 134a, unlike millions of satisfied car owners that have converted to 134a from R12 without such alterations.

 

[MitsuBoost]

I'm sure people will swap out their compressors and dryers just to convert to 134a, unlike millions of satisfied car owners that have converted to 134a from R12 without such alterations.

actually transdsm is quite correct, simply replacing r12 with r134a without replacing any components will barely feel cooler than the outside air. To do it proper you must replace the receiver /dryer at the minimum to get any real cooling. Ive tried what you are about to try several times on several different cars including my own... no good!!!

 

[TransDSM]

I'm sure people will swap out their compressors and dryers just to convert to 134a, unlike millions of satisfied car owners that have converted to 134a from R12 without such alterations.

Just as I am sure people will vent to the atmosphere on their cars without the right setup, or up the boost without supporting mods, doesn't mean it's the proper way to do it. I am just giving my knowledge based on experience. I laid out some pointers for people looking to get the best performance and life out of their AC system after converting.

 

[Sotarts]

I'll just speak for myself. I've recharged my '93 Chevy van, '89 Cougar, '90 laser and my brother's Ford Probe to 134a, and results were beautiful. Never had to recharge again and AC air was very cold.

Perhaps people that end up with bad results don't properly evacuate the system and neglect the system by not using proper amounts/types of oils/conditioners, and by not maintaining the system throughout the year by runing the AC system few times per month. Of course, no one will admit that...

 

[TransDSM]

Which is why I asked what was the reason for draining his R-12 system originally. My car still uses R-12 and still comes out ice cold. Most properly maintained systems will last you a long time.

Before converting a working R-12 system do a leak test to make sure the system is sound. The cheapest way to convert is to buy the adapter kit with the schrader valve adapters and the dryer/accumulator should be replaced. R-12 systems being a CFC system use a dessicant called XH-5. This is not compatible with the HFC based 134A which will eat through the bag releasing the dessicant pebbles into the AC system. A XH-7 dessicant must be used in a 134A system which is what all new over the counter dryers are. As stated the system must be completely evacuated and cleaned to remove an of the mineral oil that R-12 uses. Most compressor failures after conversion usually stem from improper lubrication. The R-12 mineral oil is NOT compatible with the R-134A refridgerant. Then when charging the system with R-134A fill to 80-90% capacity of the R-12. Once finished run another leak test to ensure no leaks.

Now in my opinion if you are going to convert the system you might as well do it completely. This way you can get years of enjoyment out of it without any headaches or added costs later. The R-12 hoses are not barrier hoses as the 134A ones are. You can use the existing ones as long as they weren't the problem originally. If you have to replace the hoses replace them with a barrier style. The compressor will still operate with R-12 but it is a good idea to replace it now. R-134A operates at a higher pressure than the R-12 system which can lead to shortened life when used with a compressor that might not be designed for these pressure ranges. The existing O-rings can also be used but remember the seals are older so sometimes when moving parts of the system around you might start leaks at connections. If you do replace the O-rings the new ones sold at stores should be compatible with R-134A.

So my question to the original poster is why are you changing out the R-12 in your car? If it's not working properly that means there is a leak that needs to be found. And if there is a leak then replacing the components I suggested would be a wise thing to do at this point.

 

[Cheks_Talon_TSi]

My A/C system was recharged with R-134a last year on a "profesional" A/C center. So I guess they do all necessary changes (I Haven't worriied about that, until today )... They told me that car doesn't have any leak, but one week ago I notice that my A/C wasn't cooling properly (before that, It was making its job excellent).

Yesterday before recharging the system I found out that the low pressure port (on top of the compressor) seems to be leaking... With the A/C ON, I saw that the port seems to left like a "spray vent". So I guess the port was ventilating the Refrigerant to the atmosphere and that's why I lost the pressure

I haven't reffiled with the can I bought because I guess the leak will continue, so my question is, can I change that port? or what should I do???

I appreciated a lot all of your comments...

Cheks