However, even this lower ozone depletion potential is no longer considered acceptable. It will be phased out soon under the Montreal Protocol, to be replaced by refrigerants with zero ozone depletion potential such as propane (R-290), and other refrigerants (even though they don't have very similar properties): R-410A (an azeotropic mixture of difluoromethane and pentafluoroethane), R-507A, R-134a (1,1,1,2-tetrafluroethane) and R-409A.
An additional environmental concern regarding chlorodifluoromethane, as well as some of the proposed replacements, is their global warming potential. The global warming potential of chlorodifluoromethane is 1700 (1700 times that of carbon dioxide). HFCs such as R-410A have high global warming potential, whereas that of propane (R-290) is only 3.
The US EPA has enacted regulation which will phase out the use of HCFC-22 in the near future. Air conditioning manufacturers will no longer be allowed to sell R22 equipment as of January 1, 2010. In the aftermarket service business, the allocation rights for producers who manufacture R22 will be cut each year making the remaining R22 supply potentially smaller than the service demand for the product. This could make R22 scarce in the future, and drive prices to consumers higher.
CALL 0800 479 8011 FOR FREE R22 PHASE-OUT ADVICE