Which of the following refrigerants has a higher operating pressure at the same temperature compared to R-12?

R-22 operates at a higher pressure than R-12 at the same temperature due to its thermodynamic properties and molecular structure. R-22, a hydrochlorofluorocarbon (HCFC), is designed to perform efficiently in many applications while maintaining a higher saturation pressure, which allows it to be more effective in certain cooling conditions compared to R-12, a chlorofluorocarbon (CFC).

Understanding the different types of refrigerants can also help clarify why other options do not meet the criteria. For example, R-134A, while used in similar applications, operates at lower pressures than R-22 at the same temperature. R-744, which is carbon dioxide, has significantly different property characteristics, functioning at much higher pressures but with variations in temperature profiles. R-404A is a blend of refrigerants that also operates under high pressure, but its pressure at equivalent temperatures to R-12 can differ based on the mixture of gases it contains. As a result, R-22 is specifically noted for maintaining a higher operating pressure than R-12 under identical temperature conditions.