R-401A: A retrofit blend for R-12 refrigeration systems. The pressure and system capacity match R-12 when the blend is running in a 10°F to 20°F evaporator, and there is typically an 8°F temperature glide in the evaporator. Applications: direct expansion refrigeration and air conditioning systems designed for R-12 or R-500; good success in any size system, minor adjustment of controls needed. Discharge pressure increases compared to R-12, also slight increase in discharge temperature, however the increases are not as severe as some other retrofit blends. There is a drop in capacity at lower temperatures. R-152a content, an HFC, hurts the miscibility with mineral oil. It is recommended to change some of the oil to alkylbenzene unless the system is small and running at higher evaporator temperatures.