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Before I start up my topic I will like to explain what the word refrigerant
means and other things that I fill you have to know more on the subject matter.
What are refrigerants? Refrigerants are fluids that absorb heat at low
temperatures and rejects heat at higher temperatures. The principles of
refrigerant allow for heat pumps and straight air conditioners to function
properly; because of their pressure temperature relationship. This relationship
allows for heat transfer.
In the HVAC industry refrigerants are given a trade name known as
"R" names. Examples of these names are R22, R134a, and R502. These
names help to describe the different types of refrigerants. Refrigerants have
various chemical make ups, along with different properties. Some refrigerants
are only able to work in high pressures while others use low pressures to
There are three main make ups of refrigerants that are currently used.
Hydrogenated Fluorocarbon Refrigerants (HFCs), which is made up of hydrogen,
fluorine, and carbon. Because they do not use a chlorine atom (which is used in
most refrigerants) they are known to be one of the least damaging to our ozone.
Hydrogenated Chlorofluorocarbon Refrigerants (HCFCs), which are made up of
hydrogen, chlorine, fluorine, and carbon. These refrigerants contain minimal
amounts of chlorine; they are not as detrimental to the environment as some
other refrigerants. Chlorofluorocarbon Refrigerants (CFCs), which contain
chlorine, fluorine and carbon. These refrigerants carry high amounts of
chlorine so they are known for being the most hazardous to the ozone layer.
Sometimes refrigerants consist of a two or more chemical compounds. These
blends break down into two types: Zoetrope’s
and Azeotropes. Zeotrope A zeotrope
a liquid mixture that obeys Raoult's
. It shows no maximum or minimum when vapour pressure is plotted against
the composition at a constant temperature.Zeotrope refrigerant mixes are mainly
made of three different types of refrigerants. The characteristic that
describes this type of refrigerant is that all three refrigerants keep their
own properties; they act as 3 individual refrigerants. Azeotropes are mainly a
blend of two refrigerants. The property that defines this type of refrigerant
is it acts as a single refrigerant. This effect the boiling points of both
types of refrigerants.
The most important fundamentals of refrigerants before expanding into how
they work. This key principle is that refrigerants do not make things 'cold'
they remove heat. This principle is preached in the HVAC industry. It is a
common misunderstanding of homeowners and technicians.
A pressure temperature relationship is a way of describing the specific
temperature that relates directly with the pressure of a substance. This allows
control of refrigerants boiling temperatures. Controlling a refrigerants
boiling temperature allows for proper heat transfer.
Heat transfer is when heat from one place is transferred to another place,
this is also referred to as a refrigerant cycle. Generally we control heat
transfer through air, water and refrigerants.
This type of heat transfer happens through conduction. Conduction is when
heated molecules, with lots of movement, collide with slow moving molecules.
The warmer molecules, fast moving, always move towards the cooler ones, or the
slow moving molecules.
Refrigerants are sold in disposable container that includes a check valve.
This limits the reuse of old refrigerants and prevents mixing refrigerants.
Refrigerants are identified by a standard color code. The labels also contain
information on which type of refrigerant is in the container along with any
safety hazards there are.
There are several safety hazards when handling refrigerants. In order to
help prevent damage to the ozone, technicians are required by law to become EPA
certified. There are four (4) main types of certification; Type I, Type II,
Type III, and UNIVERSAL. Type I includes small appliances such as
refrigerators. Type II includes high pressure appliance with the exclusion of
small appliances such as split-systems. Type III includes low pressure systems
such as chillers. A Universal certification includes all three types of
certifications. For more information on refrigerants, their properties, how
they effect the environment, and becoming certified.