How Your Air Conditioner Works to Cool Your Home

The first modern air conditioning system that we know and appreciate today, was developed in 1902 by Willis Carrier. Back then, a printing company needed an air conditioning system to resolve a humidity problem. Now, many homes across the nation rely on air conditioners to keep them comfortable and safe.

Knowing how your air conditioning unit works can help improve efficiency, reduce operating costs, and extend service life.

Air Conditioning Parts

Understanding how your air conditioning unit works begins with familiarizing yourself with some of its different parts. While many parts work together to provide cooling effects, these are the four main components of any air conditioning unit:


Refrigerant is a chemical compound that can transition from liquid to gas and gas to liquid. This substance also known as “coolant.” Coolant works to transfer heat and humidity out of your home.

Evaporator Coils

Evaporator coils are imperative to keeping your home cool and comfortable. This component is responsible for removing all the heat and moisture inside your home to keep it cool. The coils must always be cleaned to ensure your unit operates efficiently.

Condenser Coils

Condenser coils are the main component of your outdoor unit. These coils are responsible for taking the heat from the evaporator coils and releasing that unwanted heat outside.


For most units, the compressor is located on the outside of your home and on the inside of your air conditioning unit. The compressors job is to collect the heat from your refrigerant and disperse it through the condenser coils.

Air Conditioning Process

Now that you’re familiar with the major components of your system, let’s understand how your air conditioner works.

Step 1: Thermostat Signals Need for Cooling

The cooling process starts when your thermostat senses that the temperature inside your home needs to be lowered and sends a signal to your HVAC system to start running.

Step 2: Refrigerant Absorbs Heat

Your refrigerant will begin to draw in and absorb the warm air from inside your home. This will result in the production of cooler air while the refrigerant becomes warmer.

Step 3: Fans Blow the Cool Air Back Into Your Home

The fan from your unit will push the cold air to the evaporator coils and back through your vents into your house.

Step 4: Refrigerant Releases Heat Outdoors

The heat that the refrigerant absorbed moves to the outdoor unit and is released through the condenser coils. This process will continue until the refrigerant has reached an equilibrium.

Step 5: Fans Blow the Hot Air Out

Strong fans will blow the air to the condenser coil to assist in the cool-down process and quickly release the heat outside.

Step 6: Cold Refrigerant Travels Back to the Unit

Your compressor will start to pump the refrigerant back into your home once the air is cooled down. The process will continue until your thermostat senses that the desired temperature has been achieved.

In summary, your air conditioner removes the heat from inside your home until the air is cool enough to reach the desired temperature.


Familiarizing yourself with how your air conditioning system works, can help you save money for future repairs. The HVAC experts at Chas Roberts are ready to help and assist you with all your heating and air needs.

Chas Roberts is the oldest and largest family-owned residential HVAC company in Arizona and has been in business for over 75 years. Contact us for quality, reliable service.