What is the typical refrigerant used in most residential air conditioning systems?

R-410A is the typical refrigerant used in most residential air conditioning systems today. It is a hydrofluorocarbon (HFC) blend designed to replace R-22 due to R-22's ozone-depleting properties. R-410A operates at higher pressures than R-22, allowing for more efficient heat transfer and better cooling performance in residential applications.

The choice of R-410A has been influenced by various regulations aimed at reducing substances that harm the ozone layer. As a result, after 2010, the production and importation of R-22 for newly installed systems have significantly diminished, making R-410A the standard for new residential air conditioning units. This shift not only aligns with environmental standards but also contributes to the overall efficiency and performance of the air conditioning systems.

In contrast, R-22 was once widely used but is being phased out due to its environmental impact. R-134A is more commonly found in refrigeration applications and automotive air conditioning, while R-290 (propane) is a natural refrigerant that is often used in specific applications but is not as widespread in residential air conditioning systems.