Which zeotropic refrigerant blend is used as a replacement for R-22 in air-conditioning applications, but operates at a higher temperature and pressure?

R-410A is a zeotropic refrigerant blend that was specifically developed as a replacement for R-22 in air-conditioning applications. One of its key characteristics is that it operates at a higher pressure and temperature compared to R-22. This makes it suitable for newer air-conditioning systems designed to handle these conditions, while also providing better efficiency and enhanced cooling capabilities.

R-410A is a mixture of R-32 and R-125, and being a zeotropic blend means it has different boiling and condensation points for its components, which influences its thermodynamic properties and efficiency within the refrigeration cycle. Its higher operating pressure allows it to achieve a greater heat transfer efficiency, thus making it more effective in modern HVAC systems compared to R-22.

The other refrigerants mentioned, such as R-600a and R-290, are hydrocarbon refrigerants used primarily in smaller systems and are not direct replacements for R-22 due to compatibility and efficiency issues. R-404A, while also a refrigerant blend, operates under lower pressures than R-410A and is not primarily used as a replacement for R-22 in standard air-conditioning applications.

Thus, R-410A is recognized as the appropriate choice due to its appropriate temperature and