HCFC-22 ( also known as R-22) has been the refrigerant of choice for residential heat pump and air-conditioning systems for more than four decades. Unfortunately for the environment, releases of R-22, such as those from leaks, contribute to ozone depletion. In addition, R-22 is a greenhouse gas and the manufacture of R-22 results in a by-product ( HFC-23) that contributes significantly to global warming. As the manufacture of R-22 is phased out over the coming years as part of the agreement to end production of HCFCs, manufacturers of residential air conditioning systems are offering equipment that uses ozone-friendly refrigerants. Many homeowners may be misinformed about how much longer R-22 will be available to service their central A/ C systems and heat pumps. This fact sheet provides information about the transition away from R-22, the future availability of R-22, and the new refrigerants that are replacing R-22. This document also assists consumers in deciding what to consider when purchasing a new A/ C system or heat pump, or when having an existing system repaired.