A/C oil recharge required?

[Sanch]

I have a leak in my 97 Explorer's A/C system. Since I haven't found it yet, I keep having to add freon. My question is, if I'm losing the R134a, then aren't I also losing the oil? And if so, how do I know how much I need to add?

 

[Triton46]

I have a similar question, so I'll just hang on to your thread.

Mine was leaking R-134a and oil from one of the crimped rubber hoses. I used a can of leak fix/conditioner/dye which seems to have stopped or slowed the leaks. I am wondering how/where to drain the oil and how much/where to add new oil once things are sealed up and vaccuumed.

To help with your question though, the only way I have found to tell is to listen to your compressor. If it sounds like it is grinding or chattering...you should probably add some more oil. I would do this is small increments with pressure guages to insure you don't overfill the system.

 

[Slick Rick]

Freon.... isn't that the refrigerant that is extremely bad for the ozone layer? Don't only the older cars use that, like the ones in the early 80's, and after that point, didn't cars use a safe refrigerant? None of the explorers use freon , not even 91 ones. Someone please correct me if I am wrong.

 

[Triton46]

Someone please correct me if I am wrong.

You're wrong. The Explorers were not switched over from R-12 to R-134a until 94. Many of us have converted our existing systems to run on R-134a or an environmentally friendly coolant.

 

[Slick Rick]

Thanx Triton! Ya learn something new every day. So I guess R-12 is another name for Freon, yes?

 

[Triton46]

Yes, r12 is freon however I have heard R-134a and R22 called Freon also.

 

[Sanch]

Please don't take this the wrong way, but can we get back to the question at hand? I know I started all of this by referring to it as freon, but I'm still hoping someone can help me in determining how much oil I need to add...thanks.!

 

[DaleG]

Let me start by saying that I am no AC EXPERT!.
But from what i have learned if you are losing freon then you also lose a little oil. So yes you probably should add a little oil. Most systems usually hold about 7-8 oz of oil total, for whole system. When replacing ac components it is recommended to add oil proportionally to each component that is replaced. Typically Accumulator gets 2 oz, condenser 2 oz, evaporator 1oz, and the remainder to the compressor. Keep in mind this is while system is opened and parts are being replaced. If you are just adding freon to a leaking system then there is no way to know how much oil is still in the system. What I would do is buy a can of freon that has oil mixed in the can, usually 2 oz, and charge system with that. It should add oil proportionally with the freon.
The absolute best thing to do is find and repair the leak and add proper oil quantities while system is open, then you know for sure
There is an automotive a/c message board that is very helpful, but the techs on there Will tell you to repair the leak and fix system properly.
The link is www.aircondition.com
Just my .02 !!

Good luck

Dale

 

[Triton46]

Me sorry Sanch.

I am a regular at www.aircondition.com . Lots of good info over there.

 

[Slick Rick]

Me too Sanch

 

[Sanch]

No problem guys! I'm glad there are people here that participate as much as they do on this forum.

 

[FrankRizzo]

Ha-Ha . . . . I beat Robb to the post!

Freon is a brand name like "kleenex" It's really called refrigerant.

The only true way to get the correct oil charge back in is to recover all the refrigerant, and put the system on a vacuum pump for several hours or even overnight. Then recharge the system back to the correct refrigerant and oil level per the factory. Refrigerant and refrigerant oil mix and travel thru the system together, so you do loose oil with refrigerant.

Since this in a major PITA, just add an ounce or two to whe recharging. If your system holds 3lbs refrigerant and 9oz oil, then it leaks, and you add 1 lbs of refrigerant to clear the sight glass, add about 3oz oil.
Make sure you get the right oil for your system, different refrigerants use different oils.

Don't leave the oil sitting around and open. They are very hygroscopic.