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Auto A/C refrigerant oil is all the same, right?
Maybe you should take a closer look!

More often than not, discussions about refrigerant oils  for auto A/C systems lead to long debates. Even after all is said, there are usually more questions then answers. Part of the problem is that oil breakdown and contamination are not easily seen  when the oil is circulating in your vehicle's air conditioning system. Of course, the system is sealed, it's under pressure and there is only between 8-12 oz. in the typical automotive A/C system. So we decided to do a simple oil test that would help illustrate what happens to refrigerant oils when they become contaminated with moisture (or water).

Because PAG (Polyalkylene Glycol) oils are so widely uses, we decided to compare a typical PAG 100 Viscosity oil to Polymax2 refrigerant oil. Both oil samples were new, unopened bottles. We also used red and blue food coloring in our water samples to help tell the difference between the water and the oil. We're sure You will be truly surprised with what we found.

SAMPLE OIL #1: Typical PAG Oil (Polyalkylene Glycol) :
PAG oil is commonly used in R-134a automotive A/C systems. It is usually sold in metal cans because it is very hygroscopic. What's hygroscopic and why does it matter? Hygroscopic means that it absorbs moisture. That will cause problems for automotive A/C systems because the moisture, when mixed with the refrigerant will cause harmful acids to form. Those acids will corrode your A/C system from the inside causing large amounts of debris that restrict refrigerant flow. What's worse is that the corrosion will cause leaks in condensers, evaporators and other metal (aluminum) components.
SAMPLE OIL #2: Polymax2 auto A/C refrigerant oil :
Polymax2 Refrigerant oil is unique. Not only does this oil provide other benefits to your vehicle's A/C system, it's even non-hygroscopic. That means it will NOT absorb moisture. In fact, Polymax2 is formulated to repel moisture!
Here's the start of our oil test using PAG 100:
Typical PAG 100 refrigerant oil and water with blue dye. This was the start of our auto A/C refrigerant oil test! We simply poured the PAG oil into the water sample. Although we didn't measure exact quantities, we used a mix of about 50/50 PAG oil and water. Our PAG oil sampe was new and unopened. It immediately mixed with the water as soon as we poured it into our test sample. We used a typical PAG oil (8oz. bottle, never opened before and factory sealed). With a small glass jar of tap water we added blue food coloring to help demonstrate the results. Then we simply poured the PAG oil into the water. The results are incredible!
Typical PAG oil and water (dyed blue) Then we poured the PAG into the water. The water and
oil mixed immediately!
Take a close look at the test photos here or click the images above (left).
The PAG oil began to mix with the water immediately. The oil was absorbing the water as we photographed it. Replacing the cap on the jar, we shook the water and PAG oil sample vigorously for about 30 seconds. After standing for 1 minute, we photographed the sample in front of a light to best demonstrate how well the oil and water mixed. Even after letting the sample stand for over 48 hours, the mixture remained mixed.

We repeated that with Polymax2 Refrigerant oil:

We did the identical test with Polymax2 refrigerant oil. The only difference is that we used red food coloring in the water. Even as we poured the Polymax2 oil into the water, we could see that they began to separate immediately. There was simply no mixing moisture (or water) with Polymax2!
Polymax2 oil and water (dyed red) Like before, we poured the oil
into the water.
Polymax2 would NOT mix! Take a close look at the test photos here or click the images above (left).
We capped the oil/water sample and shook it vigorously for 30 seconds. Letting it stand, the Polymax2 separated immediately from the water. These four photos were taken over a 60-90 second time span.
Vigorous shaking for over 30 seconds to mix the water and oil

As soon as we stopped shaking, the oil began to separate

60 seconds later, most of the oil had clearly separated

90 seconds later it was almost all completely separated again

Take a close look at these test photos here or
click the images above.

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