Final answer:
HFC refrigerants usually require hydrofluorocarbons (HFCs), which are a family of lubricants.
Step-by-step explanation:
HFC refrigerants usually require hydrofluorocarbons (HFCs), which are a family of lubricants. HFCs are synthetic chemical compounds that are used as replacements for chlorofluorocarbons (CFCs) in refrigeration systems. They are nontoxic, nonflammable, and noncorrosive, which makes them ideal for use in air conditioning and refrigeration.