How Does an Air Conditioner Work?

July 18, 2016

The summer season is in full swing with record temps across the country, and with the vast majority of homes having some kind of air conditioner, it’s the best way to escape the sun. As you are relaxing in your comfortably cool home or office, appreciating that your air conditioner functions, let’s take a peek at how an average AC system works.

The Basics

Your air conditioner works the same way as your refrigerator, but obviously compared to keeping a little space cool, it has to work to cool down your whole house. Both use a refrigerant that adapts easily from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a consistent circle from the outside to the interior of your house. It goes into the home as a sub-cooled liquid that evaporates and assembles or absorbs heat from the air within your house, expands back into vapor, then returns to the outside condensing unit where it dissipates the heat and is switched back to a sub-cooled liquid.

The Components

Your AC system is made of four key pieces: an evaporator coil, a compressor, a condensing coil, and an expansion valve or metering device.

The part where your refrigerant evaporates from a sub-cooled liquid to a super-heated vapor is called the evaporator coil, which may be inside your home, in your attic, or situated in the garage. As warm indoor air is moved throughout the cold evaporator coil, heat is pulled from the air…and the cooled air is blown throughout your home.

From the evaporator coil, the now super-heated vapor refrigerant flows to the compressor based in your exterior condensing unit. The compressor increases the pressure of the vapor until it shifts into a hot, high pressure vapor. The now super-hot vapor goes into the condenser coil where a smaller amount hot air blows across the coil, removing heat to the outdoors, and switches the refrigerant to a sub-cooled liquid. The sub-cooled liquid refrigerant is pushed to the indoor evaporator coil where, through an expansion valve or metering device, the process is replicated.

Your air conditioner is a constant loop of physics at work. We realize the important thing to you likely isn’t what happens behind the scenes, but that it’s operating correctly. If you’d like to know the inner workings or just about remaining cool, give our technicians a call at 270-358-3167. We will partner with you and the laws of physics to confirm you cool this time around.