How Does AC Work?

The first modern air conditioning system made its debut in 1902. Since that time, there have been considerable improvements in the technology. Today, there are many types of air conditioners to choose from. But, for all those wondering “How does AC work?” the answer is that all of these different systems operate on the same basic principles and processes. It all starts with the laws of thermodynamics.

What are the laws of thermodynamics?

The three laws of thermodynamics define the characteristics of thermodynamic systems. To answer the question “how does AC work?” the first law is the most important one. The first law acknowledges that heat is a form of energy. Heat energy is subject to the principle of conservation of energy. Therefore, heat energy cannot be created or destroyed. It may, however, be transferred from one place to another.

In other words, the central AC that keeps your home comfortable during the summer cannot destroy the hot air inside the home. Instead, it works by transferring hot air and humidity to the exterior of the home. The central AC system also pushes cooler air back into the home after processing.

What is the anatomy of central AC?

Before diving into the details of the answer to the question “how does AC work?” you’ll need a basic understanding of the anatomy of the system. Central ACs consist of two main components: the indoor unit and the outdoor unit. These are connected together. Typically, the outdoor unit consists of a compressor and a condenser. The indoor unit is the air handler or furnace. Here’s a closer look at the main components of a central AC system.

  • Thermostat: Controlling the operation of the system, the thermostat tells it when to turn on and off.
  • Condenser coil: Located in the outdoor unit, the condenser coil releases heat into the outdoor air.
  • Compressor: Located in the outdoor unit, the compressor is a pump that shuttles refrigerant between the condenser and evaporator to chill the air taken from indoors.
  • Evaporator coil: Housed in the indoor unit, the evaporator coil uses refrigerant to remove heat and humidity from the air.
  • Fan: The outdoor fan blows air at the condenser to encourage the heat to dissipate outdoors.
  • Blower: In the indoor unit, the blower fan moves air over the evaporator to push away the chilled air.

Another important AC component is the ductwork, which distributes chilled air throughout the home. In addition, the AC filter removes particulate matter from the air. The removal of particulate matter is significant because heat clings to these particles in the air. They also affect indoor air quality.

Indoor unit: how does AC work?

Inside the home, the thermostat continuously monitors the indoor air. When the thermostat determines that the air is getting too hot, it signals the indoor and outdoor units to turn on. When the indoor fan kicks on, it suctions hot air from the home into the return air ducts. The air is then filtered to remove particulate matter.

Then, the air passes over the evaporator coil. This coil contains liquid refrigerant. The liquid refrigerant converts to a gas as it absorbs the heat from the air. This process chills the air by transferring the heat to the refrigerant. Then, the blower fan pushes the chilled air into the ductwork. From there, it can be distributed throughout the home.

Outdoor unit: how does AC work?

Since the indoor unit is responsible for chilling the air, you might be wondering why the outdoor unit is necessary at all. The outdoor unit has one main responsibility: to release the heat transferred from the indoor air. When the heat from the indoor air transforms the refrigerant from liquid to gas, this gaseous refrigerant exits the house through copper tubing.

The gaseous refrigerant then enters the compressor outdoors. The compressor pressurizes the refrigerant and sends it into the condenser coil. A fan pulls air from the outdoors through the condenser coil, allowing it to absorb the heat from the refrigerant. The heated air is released outside, along with humidity. As this process occurs, the refrigerant transforms from a gas back into a liquid.

Next, the liquid refrigerant goes back indoors through copper tubing. It goes through an expansion device. This device controls the entry of the refrigerant into the evaporator coil. Inside the evaporator coil, the refrigerant will once again absorb heat from the indoor air.

Now that you know the answer to the question “how does AC work?” you’re probably looking forward to escaping the heat with some freshly chilled air. Why not choose the HVAC company that is number one in Southern Arizona? Intelligent Design is a veteran-owned air conditioner installation and service company known for exceptional customer service and affordable rates. Call our office in Tucson at (520) 462-1538.