How Does an Air Conditioner Work?

July 18, 2016

Summer has arrived with record highs across the country, and with the vast majority of homes having some type of air conditioner, it’s the ideal way to beat the heat. As you are sitting in your comfortably cool home or office, appreciating that your air conditioner runs well, let’s take a peek at how a typical central heating and cooling system works.

The Basics

Your air conditioner runs the similar to your refrigerator, but understandably compared to keeping a single space cool, it has to cool your entire home. Both use a refrigerant that changes swiftly from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a constant ring from the outside to indoors. It goes into the interior as a sub-cooled liquid that evaporates and assembles or takes in heat from the air within your house, expands back into vapor, then back 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 built of four main components: an evaporator coil, a compressor, a condensing coil, and an expansion valve or metering device.

The component where your refrigerant evaporates from a sub-cooled liquid to a super-heated vapor is called the evaporator coil, which may be indoors, in your attic, or located in the garage. As warm indoor air is blown across the cold evaporator coil, heat is removed from the air…and the colder air is blown throughout your home.

From the evaporator coil, the now super-heated vapor refrigerant goes back to the compressor stationed in your exterior condensing unit. The compressor raises the pressure of the vapor until it changes into a hot, high pressure vapor. The now super-hot vapor goes into the condenser coil where less hot air blows past the coil, eliminating the heat to the outdoors, and returns 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 movement. We know the important thing to you likely isn’t what happens behind the scenes, but that it’s functioning successfully. If you’d like to think about the process or just about remaining cool, give our experts a call at 734-363-8907. We will partner with you and the laws of physics to confirm you cool this summer.