Which type of refrigerants use synthetic oils for lubrication because they cannot be mixed with mineral oils?

Refrigerants that require synthetic oils for lubrication because they are incompatible with mineral oils primarily include HFCs (Hydrofluorocarbons). HFCs do not mix well with mineral oils due to their molecular structure and chemical properties; hence, synthetic oils are necessary to ensure proper lubrication and system efficiency.

Using synthetic oils helps to maintain the performance of the compressor and other components in systems using HFCs. Synthetic oils are designed to have properties that accommodate the high operating pressures and lower vapor pressures characteristic of these refrigerants. This compatibility ensures that lubrication is effective, minimizing wear and extending the life of the compressor.

CFCs (Chlorofluorocarbons) and HCFCs (Hydrochlorofluorocarbons) can be mixed with mineral oils, making them less reliant on synthetic oils for lubrication. Therefore, while options mentioning CFCs and HCFCs may influence the overall understanding of refrigerant oil compatibility, they do not necessitate synthetic oils as HFCs do.