For which purpose is polyolester oil specifically recommended?

• A. CFCs
• B. HFCs
• C. HCFCs
• D. All oil types

Answer: (B)

Polyolester oil is specifically recommended for use with HFCs (hydrofluorocarbons). This type of oil has good compatibility with HFC refrigerants, which are commonly used in modern refrigeration and air conditioning systems due to their lower ozone depletion potential compared to older refrigerants like CFCs and HCFCs.

The chemical structure of polyolester oil allows it to effectively lubricate the compressor in systems that use HFCs, which are often more polar than the oils traditionally used with CFCs. This compatibility ensures better performance and longevity of equipment.

Other refrigerants mentioned, such as CFCs and HCFCs, typically use mineral oils or other types of lubricants, making polyolester oil less suitable for systems operating with those fluids. Thus, the specific recommendation of polyolester oil for HFCs is based on chemical compatibility, performance, and efficiency in those systems.