ESCO Air Conditioning Practice Exam 2025 – Complete Study Resource

The common refrigerant used in modern air conditioning systems is R-410A. This refrigerant has become the standard for many residential and commercial air conditioning systems because of its efficiency and low impact on the environment compared to older refrigerants.

R-410A is a hydrofluorocarbon (HFC) blend that does not deplete the ozone layer and operates at higher pressures, which allows for better energy efficiency in cooling performances. It also has a higher thermal conductivity than older refrigerants, leading to improved heat transfer and overall system efficiency. The shift to R-410A in new systems aligns with regulatory changes aimed at phasing out ozone-depleting substances like R-22 and R-12.

In contrast, R-22 is being phased out due to its ozone-depleting properties, and while it was widely used in the past, it is no longer being produced for use in new equipment. R-134A is primarily used in refrigeration and automotive air conditioning rather than in residential or commercial HVAC systems. Finally, R-12 is also an old refrigerant that has been completely phased out due to its detrimental effects on the ozone layer.

This context demonstrates why R-410A is the most relevant and common refrigerant in