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Dichlorodifluoromethane (R-12) is a colorless gas popularly known by the genericized brand name Freon (as Freon-12). It is a chlorofluorocarbon halomethane (CFC) used as a refrigerant and aerosol spray propellant .
Critical temperature in degrees Celsius Absolute critical pressure in kilopascals Since over 100,000 refrigerant blends are possible, [ 2 ] this list should only have notable refrigerants and refrigerant blends.
R-12 was used in automotive air conditioning systems until the mid-90s when production was banned by the government and replaced with a new refrigerant, R-134a. R-12 can still be bought and sold but is no longer produced. This makes R-12 very expensive and hard to find. [41] R-12’s global warming potential number is very large at about 11,000 ...
Values are given in terms of temperature necessary to reach the specified pressure. Valid results within the quoted ranges from most equations are included in the table for comparison. A conversion factor is included into the original first coefficients of the equations to provide the pressure in pascals (CR2: 5.006, SMI: -0.875).
A refrigerant needs to have: a boiling point that is somewhat below the target temperature (although boiling point can be adjusted by adjusting the pressure appropriately), a high heat of vaporization, a moderate density in liquid form, a relatively high density in gaseous form (which can also be adjusted by setting pressure appropriately), and ...
The only outside materials allowed are a temperature / pressure chart, scratch paper and a calculator. The certification exam contains 4 sections: Core, Type I, Type II, and Type III. Each section contains 25 multiple choice questions.
This ruling allows HFO-1234yf to take over in applications where ozone depleting CFCs such as R-12, and high GWP HFCs such as R-134a were once used. [65] The phaseout and replacement of CFCs and HFCs in the automotive industry will ultimately reduce the release of these gases to atmosphere and in turn have a positive contribution to the ...
Dichlorodifluoromethane (R-12 or CFC-12), the most commonly used Freon brand refrigerant prior to its ban in many countries in 1996 and total ban in 2010. 1,1,1,2-Tetrafluoroethane (R-134a or HFC-134a), one of the main replacements for the formerly widespread R-12. Opteon halogenated olefins now replacing Freons in many applications.