How Does an Air Conditioner Work?

July 18, 2016

The summer season is here with record temps across the country, and with the vast majority of homes having some kind 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 works, let’s gain some insight at how a normal AC system works.

The Basics

Your air conditioner operates the just like your refrigerator, but obviously rather than keeping a single space cool, it has to effectively provide cooler air to your whole 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 loop from the outside to the interior of your house. It goes into the house as a sub-cooled liquid that evaporates and gathers or absorbs heat from your indoor air, expands back into vapor, then returns to the outside condensing unit where it dissipates the heat and is transferred back to a sub-cooled liquid.

The Components

Your AC system is built of four main 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, in your attic, or in your garage. As warm indoor air is blown over the cold evaporator coil, heat is detached from the air…and the cooled air is driven throughout your home.

From the evaporator coil, the now super-heated vapor refrigerant returns to the compressor based in your outside condensing unit. The compressor enhances the pressure of the vapor until it changes into a hot, high pressure vapor. The now super-hot vapor enters the condenser coil where a smaller amount 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 repeated.

Your air conditioner is an endless loop of movement. We know the important thing to you might not be how your AC operates, but that it’s working the right way. If you’d like to think about the process or just about remaining cool, give our experts a call at 308-624-3485. We will team up with you and the laws of physics to keep you happy this summer.