Refrigerant
Any substance which absorbs heat through expansion or vaporization is known as a refrigerant.
Characteristics: It should be non-toxic, non-flammable, non-poisonous, non-explosive, easy to detect (leakage) and non-corrosive. It should operate under low pressure (low boiling point). There should be a minimum difference between the vaporizing pressure and condensing pressure.
Designation: The refrigerants are designated as
R(m-1)(n+1)(p)
Where m = number of carbon items
n = number of hydrogen items
p = number of fluorine items
Classification:
Group-1 refrigerants: These are considered to be the safest Refrigerants
Refrigerant no. |
Name |
Chemical formula |
R-11 |
Trichlorofluoromethane |
CCl3F |
R-12 |
Dichlorodifluoromethane |
CCl2F2 |
R-21 |
Dichloromonofluoromethane |
CHCl2F |
R-22 |
Chlorodifuoromethane |
CHClF2 |
R-30 |
Methylene Chloride |
CH2Cl2 |
R-113 |
Trichlorotrifluorethane |
CCl2FCClF2 |
R-114 |
Dichlorotetrafluoromethane |
C2Cl2F4 |
R-500 |
Azeotropic mixture | |
R-502 |
Azeotropic mixture | |
R-744 |
Carbon dioxide |
CO2 |