How Does An Air Conditioner Work?

An air conditioner operates akin to a pump, extracting heat from a room and expelling it outdoors. This process involves a mechanism with refrigerant gas, heat exchanger coils, and a compressor. The functioning of air conditioning units is rooted in a fundamental principle of physics—the absorption of heat when a liquid transforms into a gas. In essence, air conditioners transfer heat from the interior of a room to the exterior. Let’s delve into the workings of this intricate machinery that ensures your comfort.

The refrigerant is the most important component of an air conditioner. It is the gas that moves through the heat exchanger coils of the unit, absorbing heat within a room and expelling it outside. The refrigerant circulates within the air conditioner in a cycle of evaporation and condensation, contributing to the reduction of the air temperature inside a room. The most commonly used refrigerants include HFCs (hydrofluorocarbons) such as R410A & R32, and HCs (hydrocarbons) like R290.

An evaporator is essentially a heat exchanger coil responsible for gathering heat from the interior of a room through the use of refrigerating gas. This component is named an evaporator because it’s where the liquid refrigerant absorbs heat (from the room) and transforms into a gas. Typically constructed from copper or aluminum, these metals are chosen for their excellent heat conduction properties. The evaporator features copper/aluminum tubes through which the refrigerant flows, along with fins connected to the tubes to enhance heat transfer between the refrigerant and the outside air.

As the name implies, this component compresses the refrigerant gas into a high-pressure and high-temperature state. The compressor functions as a pump, taking refrigerant gas from the evaporator (or the unit inside the room), compressing it to elevate both pressure and temperature, and subsequently transferring the high-pressure/high-temperature gas to the condenser located outside the room.

A condenser is another heat exchanger, situated outside the room. It earns its name by being the site where hot gas undergoes condensation into a liquid. When the high-pressure/high-temperature gas reaches the condenser, a fan blows ambient air over the heat exchanger, cooling the refrigerant gas and transforming it into a liquid. This procedure enables the refrigerant to release the heat it absorbed from the room. Similar to evaporators in construction, condensers are typically made of copper or aluminum. However, they are housed in a unit outside the room.

An essential component of air conditioning units, an expansion valve is positioned between a condenser and evaporator. It regulates the quantity of refrigerant flowing toward the evaporator. The expansion valve converts high-pressure liquid refrigerant from the condenser into low-pressure/low-temperature liquid. Subsequently, this low-pressure/low-temperature liquid is directed to the evaporator, where the cycle continues.

These are the main components of an air conditioner.