How Does an Air Conditioner Work?

July 18, 2016

Summer has arrived with record heat across the country, and with the vast majority of homes having some type of air conditioner, it’s the most effective way to escape the sun. As you are relaxing in your comfortably cool home or office, thankful that your air conditioner runs well, let’s look at how a typical central heating and cooling system works.

The Basics

Your air conditioner works the same way as your refrigerator, but understandably instead of keeping a little space cool, it has to cool your entire home. Both use a refrigerant that changes simply from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a constant circle from the exterior to indoors. It goes into the home as a sub-cooled liquid that evaporates and assembles or soaks up heat from the air in your home, 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 created out of four critical parts: an evaporator coil, a compressor, a condensing coil, and an expansion valve or metering device.

The piece 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 carried throughout the cold evaporator coil, heat is pulled from the air…and the colder air is pushed within your indoor space.

From the evaporator coil, the now super-heated vapor refrigerant goes back to the compressor located in your outside 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 a lower amount hot air blows by the coil, moving 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 HVAC system is a consistent loop of movement. We know the important thing to you isn’t really how it works, but that it’s working correctly. If you’d like to know the inner workings or just about staying cool, give our professionals a call at 770-450-1539. We will partner with you and the laws of physics to keep you comfortable this season.