Refrigerants are the chemical compounds contained in an AC system that are pressurized and then expanded to attain a lower temperature. The compound is then used to cool an intermediate liquid that is used to cool the living space of a home. The two most common ones in use in residential air conditioning systems are R22, also known as HCFC-22, and 410A.
Most older AC systems use the refrigerant R22. This product works well and has been in use for over four decades. Unfortunately, it has also been identified as an ozone depleting gas and a significant threat to the ozone layer. As such, it has been outlawed. The phase out began in 2004 and is scheduled to be completed in 2020. There are, however, still stockpiles of the refrigerant and it its reclamation ensures that the gas will be used for another decade.
An alternative to this refrigerant is the far more environmentally friendly, 410A. Though this remarkable product is completely non depleting of the ozone layer, it can have a significant effect on global warming and should still be reclaimed and recycled like the product it is replacing. This refrigerant works in an identical manner to R22 but at higher pressures. For this reason, systems and technicians must be specifically built and trained to use it.
Recycling and reclamation of residential AC refrigerants are the ultimate responsibility of the homeowner. Be sure to use a reputable and environmentally responsible HVAC company when having your AC unit serviced. The immediate cost to properly care for these potentially dangerous chemicals is no more than for a routine service charge. The long term price of inadequate care, however, are far more costly.