Different Types Of A/C Compressor Oils Explained

Refueling the air conditioner in the car

Over the years, many A/C compressor oils were released on the market depending on the specifications of the car’s manufacturers. In the last couple of years, laws started to ask for more eco-friendly versions that cannot cause too much damage if leaks occur.

The A/C compressor transports the refrigerant all over the A/C system through the air compressing process. The role of oils for the air compressors is to keep them lubricated, avoid frictions so they can run continuously under high pressure and temperature conditions. These are the elements that differentiate a good oil from a bad one, the pressure, and the temperature resistance.

Also, another element to be considered when buying compressor oil is to match the manufacturer’s instructions and the components of the refrigerant. Keep reading to learn how to differentiate compressor oils and choose the best one for your car.

Mineral Oil

Very popular till the early 90s, the mineral oil or the Alkylbenzene Oil was the choice for all car owners because of its capability to mix properly with the refrigerant R-12, also known as freon. However, because of its toxic components, the R-12 has been retrieved from most markets and replaced with R-134a. Today, the mineral oil is used for cars manufactured before 95.

PAG Oils

As the mineral oil period ended, the PAG oil (Polyalkylene Glycol) made its way on the market. PAG oils, used for R-134a systems are synthetic oils, harsher than the previous oil, with a high irritative impact on the skin. Moreover, because of its hygroscopic condition, this oil should not be used as a lubricant for O-rings, refrigerant line joints, or compressor shafts. This will corrode the parts in time. Also, these oils should never be used for hybrid vehicles because oil is an electrically conductive agent.

There are several types of PAG oils, they differentiate themselves through their viscosity: PAG 46, PAG 100, PAG 150, or Universal PAG comprises all three viscosities. These oils are used for cars manufactured between 1995-2015.

Ester Oil (POE)

After the release of the two versions discussed, it was concluded that mineral oil cannot be mixed with PAG oils so to close the gap, a new A/C compressor oil appeared on the market. This transitional oil is compatible with both R-12 and R-134a systems, being stable and highly resistant to changes in pressure and temperature. As PAG oil, the ester is synthetic as well, but with different viscosity. However, given that the R-12 system was retrieved in the 94s, the oil is not an option for many.

R-1234yf Oil

As the refrigerant system changed over time, oils had to adapt quickly. Even though R-134a was dominating the US market for more than two decades, it had to be retrieved because of its high potential for heat creation. So, to avoid negative circumstances, a new system was created in 2015, R-1234yf which has its oil with the same name.

Environmental changes led to a variety of product releases on the market, and shoppers are well stocked to meet clients’ expectations. If you are unsure which oil you should be using, you can contact one of our specialists from R & Y A/C Compressors® today and learn what and how to choose.