How does an air conditioner in your car turn hot air into gold air? What makes the A/C in your minivan blow cold? When you compress gas, it creates heat. In the reverse when you expand gas it removes heat. Yes in physics their is only heat no cold, but you can negative heat, which we call cold. If you take a can of hair spray or a can of spray cooking oil and you pray our the gas/liquid out of it for a 20 seconds or more, you will notice the can starts to become cold. This is the effect of expanding gas. Your SUV’s A/C works the same way except the gas that is expanded gets to recirculate in the system and is compressed again and expanded again, over and over.
The current gas we use in Automobiles is called R134. Under the hood of your vehicle a compressor is spun by a belt connected to your engine. This compressor “compresses” the R134 gas and in doing so the gas gets very hot. The gas is then forced through a radiator in front of your regular car radiator which is call a condenser. Then the gas is filtered through the receiver drier then an expansion valve spays the gas into the evaporator core which is located under your dash. When the gas expands it creates negative heat or cold. A fan, known as a blower motor pushes cabin air past the evaporator, which is kind of like a reverse radiator, and this cools the air for the cabin. This process was invented by an American company called Carrier who developed this machine for houses. Chrysler was the first to install this system in an automobile in the mid 1030’s for limousines in New York. Since then American cars seem to have the best cooling air conditioners.