When you buy auto air conditioning parts from us, you get over a decade of
technical knowledge to go with the quality parts. We have created our "How To"
section to share that AC knowledge with you. We recommend using a licensed AC
mechanic for all auto repairs.
From mechanic to weekend do-it-yourself warrior, everyone has something new they
can take away from our learning section! Well enjoy the articles and videos
folks, we know they will help.
Air conditioners and refrigerators work the same way.
Instead of cooling just the small, insulated space inside of a refrigerator, an
air conditioner cools a whole car.
Air conditioners use chemicals that easily convert from a gas to a liquid and back
again. This chemical is used to transfer heat from the air inside of a car to
the outside air.
The machine has three main parts. They are a compressor, a condenser and an
evaporator. The compressor is located on the engine, because it is typically
belt driven. The condenser is located at the front of the car to take advantage
of air coming in from the moving vehicle. The evaporator is located closer to
the cabin of the car, usually under the dash or near the firewall.
The working fluid arrives at the compressor as a cool, low-pressure gas. The
compressor squeezes the fluid. This packs the molecule of the fluid closer
together. The closer the molecules are together, the high its energy and its
temperature. The working fluid leaves the compressor as a hot, high pressure gas
and flows into the condenser. If you look at the condenser, look for the part
that has metal fins all around. The fins act just like the radiator in the car
and helps the heat go away, or dissipate, more quickly.
When the working fluid leaves the condenser, its temperature is much cooler and it
has changed from a gas to a liquid under high pressure. The liquid goes into the
evaporator through a very tiny, narrow hole. On the other side, the liquid's
pressure drops. When it does it begins to evaporate into a gas. As the liquid
changes to gas and evaporates, it extracts heat from the air around it. The heat
in the air is needed to separate the molecules of the fluid from a liquid to a
The evaporator also has metal fins to help in exchange the thermal energy with the
surrounding air. By the time the working fluid leaves the evaporator, it is a
cool, low pressure gas. It then returns to the compressor to begin its trip all
over again. Connected to the evaporator is a fan that circulates the air inside
the car to blow across the evaporator fins.
Hot air is lighter than cold air, so the hot air in the car rises to the top of the
interior just like it rises to the top of a room. There is a vent there where
air is sucked into the air conditioner and goes down ducts. The hot air is used
to cool the gas in the evaporator. As the heat is removed from the air, the air
is cooled. It is then blown into the car through other ducts usually at the
This continues over and over and over until the interior of the car reaches the
temperature you want the car cooled to. The thermostat senses that the
temperature has reached the right setting and turns off the air conditioner. As
the room warms up, the thermostat turns the air conditioner back on until the
car reaches the temperature