Which of the following refrigerants is classified as an HFO?

The refrigerant classified as an HFO (hydrofluoroolefin) is R-1234YF. HFOs are a newer class of refrigerants that are designed to have lower global warming potential (GWP) compared to traditional hydrofluorocarbons (HFCs). R-1234YF, in particular, has gained popularity as a refrigerant in automotive air conditioning systems and other applications due to its lower impact on the environment.

The other options listed—R-22, R-410A, and R-134A—are all categorized as HFCs. HFCs have been widely used in many applications, but they generally have higher GWPs than HFOs, leading to a transition towards HFOs like R-1234YF in efforts to reduce greenhouse gas emissions. Recognizing the classification of refrigerants is important for compliance with environmental regulations and for making informed choices in refrigerant selection.