Refrigerant R-410A is a HFC based refrigerant which means that you do not have to be licensed as a Certified Refrigerant Technician to purchase or service R-410A equipment. R-410A can not be used to retrofit existing R-22 equipment because of the higher discharge pressure. Because of the higher pressure, different service tools are required to service equipment that is designed for the higher pressures of R-410A. R-410A is a blend refrigerant made of R-32 and R-125 at a 50/50% ratio. The refrigerant acts as a single refrigerant therefore, if there is a leak in a system, the system can be topped off instead of having to replace all of the refrigerant in the system.