How Does an Air Conditioner Work?

July 18, 2016

The popular season is here with record highs across the country, and with a lot households having some kind of air conditioner, it’s the best way to beat the heat. As you are sitting in your comfortably cool home or office, thankful that your air conditioner functions, let’s look at how an average central heating and cooling system works.

The Basics

Your air conditioner runs the just like your refrigerator, but understandably compared to keeping a small space cool, it has to cool your entire home. Both use a refrigerant that changes easily from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a constant loop from the outdoors to indoors. It goes into the interior as a sub-cooled liquid that evaporates and gathers or soaks up heat from the air in your home, expands back into vapor, then heads to the outside condensing unit where it dissipates the heat and is changed back to a sub-cooled liquid.

The Components

Your AC system is created out of four key components: 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 indoors, in your attic, or located in the garage. As warm indoor air is carried across the cold evaporator coil, heat is removed from the air…and the cooler 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 increases the pressure of the vapor until it turns into a hot, high pressure vapor. The now super-hot vapor meets the condenser coil where less hot air blows past the coil, eliminating the 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 redone.

Your HVAC system is a consistent loop of movement. We understand the important thing to you likely isn’t what happens behind the scenes, but that it’s functioning correctly. If you’d like to talk science or just about keeping cool, give our technicians a call at 505-445-1250. We will work with you and the laws of physics to confirm you happy this summer.