The invention of air conditioning for indoor home and work spaces is one of civilization’s most enduring innovations. Yet, for as much as we rely on our HVAC units to keep our homes and workplaces cool and comfortable, many people do not know exactly how an air conditioner really works.

In this short post, learn the fundamentals of what makes an air conditioner work.

An Air Conditioner is to a Refrigerator….

In many ways, the same technology that powers your basic refrigerator is also what powers your air conditioning unit. The major difference is the size of the space being cooled.

A refrigerator is typically tasked with cooling a very small, confined space. The air conditioner installed in your average home will be required to cool a larger space. A commercial air conditioner must cool a larger space, whether it be a single office suite or an entire multi-storied building.

The Components of the Typical Air Conditioner

There are four main components that form the basis of nearly any air conditioner.

Compressor. Responsible for “compressing” the initial refrigerant (fluid) into gas.

Condensor. Responsible for condensing the compressor’s high pressure gas back into liquid.

Evaporator. Responsible for changing that liquid back into a cooler gas.

Expander. Responsible for regulating the use of the liquid/gas to keep the warm air out and the cool air in.

Refrigerant. Also called hydrochlorofluorocarbons (HCFCs), the refrigerant is the magic ingredient that helps the air conditioner regulate the air temperature within any size space.

The Refrigerant Hard at Work

The refrigerant itself acts much like water, which can be transformed into a hard substance (ice) at cold temperatures, into a gaseous vapor (fog, mist) at higher temperatures and also remain in its natural liquid state.

The action of the evaporator, compressor and condenser work to transform a certain amount of the refrigerant as needed to adjust air temperature based on the temperature of the outside air. The expander is simultaneously hard at work determining how much refrigerant may be required at any given time to maintain your desired indoor air temperature.

Different Types of HVAC Units

When air conditioning was first invented, there was not much variety to choose from in terms of the size or type of unit. But today there is a great variety to choose from.

Here are some of the many different types of HVAC units available today:

Portable. These systems are small, lightweight and freestanding.

Window. These systems can fit in a typical window frame.

Ductless (Split). These systems are typically floor or wall-mounted within a room.

Package Terminal (PTAC). These systems are often found in hotels and commercial spaces.

Central. These larger systems can cool whole homes or office buildings. They often share ductwork so they can het the same spaces when temperatures drop.

It is important to know what type of system you need for the size of the space you want to cool/heat and hire the right home or commercial AC service to install and maintain your system. If you are considering replacing or upgrading your existing unit, the same holds true. By taking the time to match the HVAC unit to the space size, you can get the most value for your money.

How Does an Air Conditioner Work?