Briton R404A Refrigerant Gas is an almost azeotropic mixture of HFC refrigerants, with zero ozone layer depletion, used in new refrigeration equipment at mid-range and low temperatures. It is also an indirect replacement (retrofit), in equipment that previously operated with R-502 and its HCFC replacements such as R-408A, DI-44, and HP80. It is mainly used in new installations with mid-range and low refrigeration temperatures. The theoretical cooling capacity is 5% lower than R-502 at evaporation temperatures of -40ºC. The coefficient of performance (COP) is between 5 and 8% lower than R-502. As superheating increases, R-404A’s COP might become higher than that of R-502. In the case of R-502 retrofits and its HCFC replacements (R-408A, DI-44), 95% of the original mineral oil or alkylbenzene must be replaced by a polyolester oil, the dryer filter and expansion valve changed, rubber O-rings replaced with plastic ones and, occasionally, the size of the condenser must be increased. When it is used as a retrofit for R-22, the safety valves also need to be changed along with any other elements calibrated to R-22 pressures.