How do refrigerators work?
Almost every household in the world has a
refrigerator. They represent the only way to easily cool foods for long
periods of time in order to eat them on a later date and prevent them from
spoiling. Yet despite so many people owning a fridge of their own, few
people actually understand how they work, and what is done to make sure that
they are able to effectively keep your food cool for extended periods of
time.
How Refrigerators Work
It should be noted before this explanation that
there are other types of fridges that work in different manners. Some use
gas and a form of heat, while others use a “heat dumping” method that
involves a complicated electronic process. Certain modern refrigerators
boast their own unique refrigeration system while older fridges may have an
outdated method. However, most refrigerators use what is known as the “vapor
compression cycle,” which is the type of refrigeration described below.
Vapor compression cycle refrigerators work using
the following method:
·
A “refrigerant” is compressed (in a
compressor) and turned into a vapor that is actually above room temperature
– warmer than 72 degrees. Note that through most of the process the
refrigerant is actually warmer than room temperature.
·
After being compressed, the vapor then
exits the compressor via high pressure, which warms the refrigerant up more
– shooting it through the coils in the back of the fridge. These coils are
known as “condensers.”
·
The condensers, are designed to
naturally cool the refrigerant back down using the cooler air of the room,
and it turns the refrigerant into a liquid – however, during this time the
liquid is still under pressure, and still above room temperature.
·
Finally the liquid is ready to leave
the condenser through an “extension valve.” When it leaves the condenser, it
travels to an area of considerably lower pressure, which forces some of the
refrigerant to evaporate immediately. The remaining heat is sucked into the
remaining liquid, while the evaporated refrigerant continues to travel
through additional tubes.
·
A fan is used to cool the evaporated
refrigerant further, making it evaporate even more. This evaporated
refrigerant then sucks in more heat from the box, making the air around it
cooler, which is then dispersed throughout the refrigerator and freezer. The
refrigerant then continues back to the originally compression cycle to start
over.
A Complicated Process That Has Proven to
Work
There is a great deal of physics that is involved
with this type of refrigeration process. While it may seem difficult to
understand at times, it has proven itself to be the best way to cycle cold
air throughout a refrigerator for a long period of time. Other modern
refrigeration methods use some form of variation of this type of system, but
in general you are going to see vapor compression cycle refrigerators on the
market because they are more efficient than many other types of
refrigerators and have proven themselves to be both a reliable and effective
method of cooling.
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