How Does an Air Conditioner Work?

July 18, 2016

The summer season is here with record heat across the country, and with many houses having some kind of air conditioner, it’s the most effective way to escape the sun. As you are relaxing in your comfortably cool home or office, appreciating that your air conditioner functions, let’s look at how a typical central heating and cooling system works.

The Basics

Your air conditioner runs the same way as your refrigerator, but understandably instead of keeping a small space cool, it has to work to cool down your whole house. Both use a refrigerant that adapts easily from liquid to gas, back to liquid again. In your air conditioner, the refrigerant is on a constant loop from the exterior to indoors. It goes into the home as a sub-cooled liquid that evaporates and collects or absorbs 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 built of four main parts: 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 located in the garage. As warm indoor air is blown across the cold evaporator coil, heat is pulled from the air…and the cooled air is blown among your indoor space.

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 shifts into a hot, high pressure vapor. The now super-hot vapor meets the condenser coil where a smaller amount hot air blows past the coil, removing 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 isn’t really how it works, but that it’s working the right way. If you’d like to think about the process or just about staying cool, give our experts a call at 928-244-8840. We will team up with you and the laws of physics to confirm you comfortable this time around.