How Does an Air Conditioner Work?

July 18, 2016

The summer season is in full swing with record heat across the country, and with the vast majority of homes having some kind of air conditioner, it’s the best way to get out of the heat. 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 central heating and cooling system works.

The Basics

Your air conditioner operates the just like your refrigerator, but obviously instead of keeping a little space cool, it has to cool your entire home. Both use a refrigerant that converts easily from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a regular loop from the outdoors to the interior of your house. It goes into the home as a sub-cooled liquid that evaporates and collects or soaks up heat from your indoor air, expands back into vapor, then heads 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 key pieces: 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 situated in the garage. As warm indoor air is moved throughout the cold evaporator coil, heat is pulled from the air…and the colder air is driven within your house.

From the evaporator coil, the now super-heated vapor refrigerant flows to the compressor located in your outdoor condensing unit. The compressor increases the pressure of the vapor until it changes into a hot, high pressure vapor. The now super-hot vapor meets the condenser coil where less hot air blows across the coil, eliminating the heat to the outdoors, and returns the refrigerant to a sub-cooled liquid. The sub-cooled liquid refrigerant is returned to the indoor evaporator coil where, through an expansion valve or metering device, the process is redone.

Your HVAC system is a constant loop of movement. We realize the important thing to you might not be how your AC operates, but that it’s functioning the right way. If you’d like to think about the process or just about keeping cool, give our experts a call at 515-344-3579. We will partner with you and the laws of physics to keep you comfortable this season.