Which oil type is specifically indicated as synthetic in the context of refrigeration systems?

In refrigeration systems, ester-based oils are specifically indicated as synthetic. These oils are created through the chemical reaction of an alcohol and an acid, resulting in a product that offers superior performance in terms of lubrication and thermal stability compared to traditional oils. Ester-based oils are known for their compatibility with various refrigerants, especially those that are environmentally friendly or have lower Global Warming Potential (GWP).

Additionally, synthetic oils, including ester-based oils, are able to withstand higher temperatures and pressures and are less likely to break down over time. This characteristic makes them particularly suitable for modern refrigeration applications where efficiency and longevity are critical.

In contrast, alkylbenzene oil, naphthenic oil, and mineral oil are generally derived from natural sources and do not exhibit the same synthetic properties or benefits as ester-based oils. These types of oils may not provide the same level of performance in the demanding environments of modern refrigeration systems, highlighting the importance of ester-based oils in enhancing system reliability and efficiency.