A variety of built-for-purpose refrigeration oils are available today, designed to work with different kinds of systems.
The two broad terms used to classify refrigerant lubricants are mineral oils and synthetic oils. In this article, we will discuss these oil types in greater depth.
Mineral refrigeration oils
Mineral oils are a derivative product. They are generated during the processes involved in refining petroleum.
Mineral oil is a useful by-product that is harvested when crude oil is being distilled to create gasoline. In terms of acting as a refrigeration oil, it was predominantly used in service with older generation refrigerants, like chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs).
Synthetic refrigeration oils
While mineral oils were suited for older models of refrigeration systems using refrigerants, when the industry began phasing out the use of HCFCs and CFCs to answer environmental legislation, new oils needed development to suit alternative refrigerants.
These next generation products are known universally as synthetic oils. These man-made oils are generated from processed petroleum and engineered to contain specific properties that enable them to work effectively with modern refrigerants.
Retrofit projects require synthetic oils, as mineral oils aren’t miscible with the latest refrigerants in use. Mineral oils don’t combine well with modern refrigerants, preventing them from performing their role.
Different synthetic refrigeration oil types
Various synthetic refrigerant oils are available, including Polyolester (POE), Polyalkylene Glycol (PAG), Alkylbenzene (AB) and Polyvinyl Ether (PVE) to match different types of refrigerants.
Refrigeration oils must be miscible with the refrigerant used so the oil can work effectively. For instance, when an oil is utilised in a system using HCFC refrigerant, it must be miscible with HCFCs.
POE synthetic oils find use in refrigeration systems that contain Hydrofluorocarbons (HFCs) better known as Freons or Hydrofluoroolefins (HFOs) refrigerants. These synthetic oils are also referred to as ester oils.
When an older refrigeration system is retrofitted to work with modern refrigerants like HFCs or HFC blends, POE oils should be used. Users should understand that ester oils are not miscible with other oil types.
PAG synthetic oil is primarily used in the onboard air conditioning systems of automotive vehicles.
AB synthetic oils are used in refrigeration systems using HCFC and CFC type refrigerants. While it’s true that these older refrigerants have now been phased out, you can still find blends that include HCFCs. As result, AB synthetic oils are used to service applications where a blend containing HCFC refrigerant is used.
Finally, PVE oils are synthetic lubricants that serve as an alternative to ester oils.
For concerns regarding refrigerant and refrigeration oil compatibility, consult your specialist lubrication distributor before buying.
