The first major phase change for refrigerants has not even been completed yet and already many are urging yet another. The long, hard, costly journey away from ozone-depleting chlorofluorocarbons (CFCs), which began in the early 90s, continues, with a 2010 step down in production and eventual phase out of hydrochlorofluorocarbon (HCFC)-22 refrigerant in new HVAC/R applications. But soon after hydrofluorocarbons (HFCs) became the established alternative, many in Europe began urging yet another costly, arduous trek – away from HFCs and toward “natural refrigerants.” The igniter behind all the commotion is the hot topic of the day – global warming.