What oil is best suited to R290 refrigerant?

For R290 (Propane) refrigerant, poly-alpha-olefin (PAO) oil, specifically SHC230, is considered the standard oil charge. However, polyalkylene glycol (PAG) oil, such as B-PAG220, can also be used for an extended application range with R290.

Understanding Oil Types for R290

The choice of lubricant is crucial for the efficient and reliable operation of refrigeration systems using hydrocarbon refrigerants like R290. Proper oil selection ensures excellent miscibility, lubricity, and chemical stability within the system.

Poly-Alpha-Olefin (PAO) Oil: The Standard Choice

• Type: Poly-alpha-olefin (PAO)
• Example: SHC230
• Suitability: PAO oils are widely recognized as the standard oil charge for systems utilizing R290 refrigerant. They offer excellent performance characteristics, including good thermal stability and a high viscosity index, which contributes to effective lubrication across varying operating temperatures. PAO oils maintain their properties well in the presence of hydrocarbon refrigerants, ensuring long-term system integrity and efficiency.

Polyalkylene Glycol (PAG) Oil: For Extended Applications

• Type: Polyalkylene Glycol (PAG)
• Example: B-PAG220
• Suitability: While PAO is the standard, PAG oils can also be used with R290, particularly for extended application ranges. PAG oils are known for their high miscibility with some refrigerants and excellent lubricating properties. Their use with R290 typically applies to specific system designs or operational parameters where their unique characteristics provide an advantage. It's important to consult equipment specifications when considering PAG oil for R290.

Comparison of Oils for R290

To summarize the recommended oil types for R290:

Always refer to the compressor manufacturer's recommendations and system requirements when selecting the specific oil type and grade for your R290 refrigeration system.