A/C: Pag oil vs Ester.

[Chris142]

I searched and did not find what I was lookin for.

Whats the general conscensus on these 2 types of oils?

I work at a radiator and A/C shop. I was the grunt guy/parts swapper. The A/C guy is gonna be out for a while and I was thrown into the A/C guy position.

We always use what ever oil the compressor manufacturrer recomends.

Usually this is Pag ISO #46,#100 and #150.

I went to an A/C class last week and the guy there recomended Ester oils over Pag oils.

He said that adding Ester oil to a system with Pag oil is a good thing.

What do ya'll think?

 

[TooManyWheels]

My reading says there is a wide range of opinions on this subject. I doubt if you will find a general consensus on this question in the industry, and if you find it on this board, it will not be a very informed one.

The simple answer is that PAG oils are more likely to come from the factory, while Esther oils are compatible with PAG and more tolerant of moisture, although maybe not quite as good in a completely dry system. Esther oils are also the preferred ones for R12 to 134 conversions because they will tolerate mineral oil remaining from when the system was R12.

But that is a generalization, and there are lots of nuances. To really be informed, look for places where the pros hang out, like http://www.ackits.com/forum/index.cfm, or the alt.hvac newsgroup (for residential and commercial, but some guys know auto A/C).

I don't mean to disrespect anyone who might be on this board, but if you are doing this for customers you will probably want more than just the one or two opinions you will get here.

[ May 03, 2004, 12:48 AM: Message edited by: TooManyWheels ]

 

[Avery4]

I prefer Ester oil over PAG oil for these reasons: better refrigerant compatibility, does not eat seals, does not absorb moisture and is non electrically conducive. The last one is only important for electric compressors, such as the ones on hybrids and appliances. However, it does not lubricate as well as PAG oil under ideal conditions.

 

[Trav]

Originally Posted By: Chris142


We always use what ever oil the compressor manufacturrer recomends.

Usually this is Pag ISO #46,#100 and #150.


What do ya'll think?


That's what I have been doing for over 40 years and it hasn't let me down yet. Look at it this way, this is a customers car not an experiment.
It works fine from the factory with that in it, it cause no issues so why frig around with it.
There is always the chance the compressor manufacturers will tell you to go scratch for the warranty if the wrong lube is used. Keep it simple and experiment on your own stuff if you feel the need.

 

[CorvairGeek]

Pro and con to both, but I believe there is not a single manufacturer of automotive compressors that recommends Ester.

 

[nthach]

Automotive HVAC preferred PAG oils over ester oils - it's more "mobile" in R-134a compared to ester and has a lower hydrolysis risk than ester despite being hygroscopic. Ester was used in the aftermarket because it's compatible with R-12 and retrofits are more likely to happen in an the aftermarket.