Which refrigerant cools better, R-22 or R-32?

Which refrigerant cools better between R-22 and R-32 depends on system design, but R-32 generally has better cooling performance in modern equipment designed for it. R-22 is an HCFC that was standard for decades and has good thermodynamic properties, moderate pressures, and good heat transfer with mineral oil. R-32, or difluoromethane, is an HFC with zero ozone depletion potential and lower global warming potential, higher thermal conductivity, higher latent heat of vaporization, and higher volumetric capacity than R-22, meaning it can transfer more heat per unit volume and achieve higher efficiency. In tests, R-32 systems show higher coefficient of performance and about 5 to 10 percent higher energy efficiency compared to R-22 in similar capacity systems, with lower refrigerant charge needed. However, R-32 operates at higher pressures similar to R-410A, about 50 percent higher than R-22, so equipment must be designed to handle it, and it is mildly flammable A2L while R-22 is non-flammable A1. You cannot compare cooling by dropping R-32 into an R-22 system because pressures and oils differ. In properly designed new equipment, R-32 cools better, more efficiently, and with less refrigerant than R-22, which is why industry has transitioned to R-32 for new mini-splits.