Air conditioning works by using a process called refrigeration to cool the air in a room when you set it to a specific temperature, such as 24°C. Here's how it typically works:
Refrigerant: The air conditioning system contains a chemical compound called refrigerant. This refrigerant has a low boiling point, which allows it to change state from a liquid to a gas and vice versa at relatively low temperatures.
Evaporation: The refrigerant is first compressed into a high-pressure, hot gas. It then passes through a coil or set of coils inside the indoor unit of the air conditioner. As the hot refrigerant passes through these coils, it absorbs heat from the indoor air, cooling the air in the process. This is because the refrigerant is much cooler than the indoor air, so heat transfers from the warmer air to the cooler refrigerant.
Compressor: After absorbing heat and becoming a hot gas, the refrigerant is then sent to the compressor, where it gets further compressed. Compressing the gas increases its temperature even more.
Condensation: The hot, high-pressure gas is then passed through another set of coils in the outdoor unit of the air conditioner. These coils are exposed to the outside air, allowing the heat from the refrigerant to dissipate into the environment. As a result, the refrigerant condenses back into a liquid state, releasing the heat it absorbed indoors.
Expansion Valve: The liquid refrigerant, now at a high pressure, passes through an expansion valve. This valve reduces the pressure of the refrigerant and allows it to expand rapidly. The expansion causes the refrigerant to become cold and turn back into a low-pressure gas.
Evaporator: The cold, low-pressure refrigerant is then sent back inside the building to the indoor unit, and the cycle starts again. The indoor unit's fan blows warm indoor air over the cold coils containing the low-pressure refrigerant. The refrigerant absorbs heat from the indoor air, cooling it down, and the cooled air is then blown back into the room, reducing the temperature and providing the desired cooling effect.
This cycle continues until the temperature inside the room reaches the desired setpoint (in this case, 24°C). The air conditioner's thermostat monitors the room's temperature and controls the cooling process to maintain the desired temperature.
In summary, air conditioning cools the room by transferring heat from the indoor air to the refrigerant through evaporation and then dissipating that heat outside through condensation. The continuous cycle of this heat transfer process allows the air conditioner to maintain a comfortable temperature inside the room.