The following shows techical data as to why it was not good for consumers, and one must ask
who really benefitted from the costly changeover!
HC12a System Versus R134a System
Hydrocarbons are the best refrigerants for existing systems whether it is an R12 system or
a R134a system and to my knowledge that has never been disputed. Hydrocarbons are non-corrosive, nontoxic,
non-ozone depleting, non-global warming, and much more energy efficient than CFC's or HFC's.
Hydrocarbons are flammable because they are LPG's (Liquified Petroleum Gases): naturally occurring compounds
which are safe for the environment, and safe for human health. Many LPG's, including natural gas and propane,
are safely used in numerous applications within homes, businesses, and motor vehicles throughout the
United States and the world.
By Charles Fox
For decades, large US. industries have utilized hydrocarbons within their air conditioning and refrigeration systems,
and have found them to be highly efficient and safe refrigerants. Use and acceptance of hydrocarbons in
motor vehicle and commercial air conditioning and refrigeration applications within the US. has been much slower.
Why is that? The refrigerant market has been controlled by the chemical industry for over 60 years and nobody
was willing to buck them as long as R12 was so cheap. We used to let it go into the atmosphere rather than
recover it. In the 1990's all of that changed. The industry realized that they could scare the people into believing
that the sky was falling. They did a very good job. Twenty years ago practically no one knew what the term freon
meant unless you worked in the industry of air conditioning or refrigeration. Now you would be hard pressed
to find someone who doesn't believe that it is destroying the ozone layer. Is it really? Freon (R12) is
4 to 8 times heavier than air. It holds together as a molecule for 130 years. How did it bounce up to 75,000 feet
to destroy the ozone? You tell me.
R134a was to be our savior and all the money and work caused the vast majority of people to believe that including me.
In 1997 I started doing some research into R134a.
What I found was almost unbelievable. R134a is extremely toxic and extremely corrosive, but that was not
the worst thing that I uncovered. R134a is combustible at 351 degrees. Many people have seen cars on the side
of the highway in the last few years that are totally destroyed from fire damage.
Most people that read this article will not want to believe what I'm saying and all I can say is that I want you
to prove me wrong.
Construction Mechanic Basic Volume 02
Refrigerants are fluids that change their state upon the application or removal of heat within a system and,
in this act of change, absorb or release heat to or from an area or substance. Many different fluids are used
as refrigerants. In recent years, the most common has been air, water, ammonia, sulfur dioxide, carbon dioxide,
Today, there are three specific types of refrigerants used in refrigeration and air-conditioning systems —
(1) Chlorofluorocarbons or CFCs, such as R-11, R-12, and R-114; (2) Hydrochlorofluorocarbons or HCFCs,
such as R-22 or R-123; and (3) Hydrofluorocarbons or HFCs, such as R-134a. All these refrigerants are "halogenated,"
which means they contain chlorine, fluorine, bromine, astatine, or iodine.
Refrigerants, such as Dichlorodifluoromethane (R-12), Monochlorodifluoromethane (R-22), and Refrigerant 502 (R-502),
are called PRIMARY REFRIGERANTS because each one changes its state upon the application or absorption of heat, and,
in this act of change, absorbs and extracts heat from the area or substance. The primary refrigerant is so termed
because it acts directly upon the area or substance, although it may be enclosed within a system. For a
primary refrigerant to cool, it must be placed in a closed system in which it can be controlled by the pressure
imposed upon it. The refrigerant can then absorb at the temperature ranges desired. If a primary refrigerant
were used without being controlled, it would absorb heat from most perishables and freeze them solid.
SECONDARY REFRIGERANTS are substances, such as air, water, or brine. Though hot refrigerants in themselves,
they have been cooled by the primary refrigeration system; they pass over and around the areas and substances
to be cooled; and they are returned with their heat load to the primary refrigeration system. Secondary refrigerants
pay off where the cooling effect must be moved over a long distance and gastight lines cost too much.
Refrigerants are classified into groups. The National Refrigeration Safety Code catalogs all refrigerants into
three groups—Group I – safest of the refrigerants, such as R-12, R-22, and R-502; Group II – toxic and somewhat
flammable, such as R-40 (Methyl chloride) and R-764 (Sulfur dioxide); Group III – flammable refrigerants,
such as R-170 (Ethane) and R-290 (Propane).
R-12 DICHLORODIFLUOROMETHANE (CCI2F2)
Dichlorodifluoromethane, commonly referred to as R-12, is colorless and odorless in concentrations of less than
20 percent by volume in air. In higher concentrations, its odor resembles that of carbon tetrachloride.
It is nontoxic, noncorrosive, nonflammable, and has a boiling point of -21.7 F (-29 C) at atmospheric pressure.
WARNING: Because of its low-boiling point at atmospheric pressure, it prevents liquid R12 from contacting the eyes
because of the possibility of freezing.
One hazard of R-12 as a refrigerant is the health risk should leakage of the vapor come into contact
with an open flame of high temperature (about 1022 F) and be decomposed into phosgene gas, which is highly toxic.
R-12 has a relatively low latent heat value, and, in smaller refrigerating machines, this is an advantage.
R-12 is a stable compound capable of undergoing the physical changes without decomposition to which it is commonly
subjected in service. The cylinder code color for R-12 is white.