<P> Commercial refrigerator and freezer units , which go by many other names , were in use for almost 40 years prior to the common home models . They used gas systems such as ammonia ( R - 717 ) or sulfur dioxide ( R - 764 ) , which occasionally leaked , making them unsafe for home use . Practical household refrigerators were introduced in 1915 and gained wider acceptance in the United States in the 1930s as prices fell and non-toxic , non-flammable synthetic refrigerants such as Freon - 12 ( R - 12 ) were introduced . However , R - 12 damaged the ozone layer , causing governments to issue a ban on its use in new refrigerators and air - conditioning systems in 1994 . The less harmful replacement for R - 12 , R - 134a ( tetrafluoroethane ) , has been in common use since 1990 , but R - 12 is still found in many old systems today . </P>
<P> Commercial refrigerator and freezer units , which go by many other names , were in use for almost 40 years prior to the common home models . They used gas systems such as ammonia ( R - 717 ) or sulfur dioxide ( R - 764 ) , which occasionally leaked , making them unsafe for home use . Practical household refrigerators were introduced in 1915 and gained wider acceptance in the United States in the 1930s as prices fell and non-toxic , non-flammable synthetic refrigerants such as Freon - 12 ( R - 12 ) were introduced . However , R - 12 damaged the ozone layer , causing governments to issue a ban on its use in new refrigerators and air - conditioning systems in 1994 . The less harmful replacement for R - 12 , R - 134a ( tetrafluoroethane ) , has been in common use since 1990 , but R - 12 is still found in many old systems today . </P>
what kind of freon is in a refrigerator
what kind of freon is in a refrigerator
Freon - 12 ( R - 12 )
Freon - 12 ( R - 12 )