Functioning of Air Conditioners

Posted by


Window and Split-system AC Units


A window air conditioner unit is a compact air conditioning system suitable for small spaces. These units are designed to fit standard window frames. When you plug in the unit and switch it on, cool air is easily produced. Upon removing the cover of an unplugged window unit, you will see that it comprises:

  • A compressor
  • An expansion valve
  • A hot coil (on the outside)
  • A chilled coil (on the inside)
  • Two fans
  • A control unit

The fans blow air over the coils to enhance their heat dissipation capability (to the outside air) and cold air (to the room being cooled).

For more extensive air conditioning applications, split-system units should be considered. The split-system air conditioner divides the hot and cold sides of the system, as shown in the diagram below.

Generally, the cold side, including the expansion valve and the cooling coil, is placed in a furnace or another air handler. The air handler forces air through the coil and directs it throughout the building using a series of ducts. The condensing unit, known as the hot side, is located outside the building.

The unit comprises a long, spiral coil shaped like a cylinder. A fan is present inside the coil to blow air through it, along with a weather-resistant compressor and control logic. This approach has evolved over time because of its low cost and reduced noise inside the house (at the expense of increased noise outside the house). Apart from the fact that the hot and cold sides are separated and the capacity is higher (making the coils and compressor larger), there is no difference between a split-system and a window air conditioner.

In warehouses, large business offices, malls, big department stores, and other large buildings, the condensing unit is usually located on the roof and can be quite massive. Alternatively, many smaller units may be present on the roof, each attached inside to a small air handler that cools a specific area in the building.

In larger buildings, especially in multi-story buildings, the split-system approach becomes problematic. Running the pipe between the condenser and the air handler exceeds distance limitations (runs that are too long start to cause lubrication difficulties in the compressor), or the amount of duct work and the length of ducts becomes unmanageable. At this point, it is necessary to consider a chilled-water system.


1. What is an air conditioner?

An air conditioner is a device that cools and dehumidifies the air in a room or building. It works by removing heat and moisture from the air, leaving behind cooler and drier air.

2. How does an air conditioner work?

An air conditioner works by using a refrigerant to absorb heat from the air inside a room or building. The refrigerant then moves outside where it releases the heat. The cooled air is then blown back into the room.

3. What are the main components of an air conditioner?

The main components of an air conditioner include the compressor, condenser, evaporator, and expansion valve. These components work together to remove heat and moisture from the air.

4. What types of air conditioners are there?

There are several types of air conditioners, including window units, portable units, central air conditioning systems, and ductless mini-split systems. Each type has its own advantages and disadvantages.

5. How do I choose the right size air conditioner?

The right size air conditioner for your space depends on factors such as the size of the room or building, the number of windows, and the amount of insulation. A professional can help you determine the right size for your needs.

6. How often should I clean or replace my air conditioner’s filter?

You should clean or replace your air conditioner’s filter every one to three months, depending on usage. This helps keep the air clean and prevents the system from working harder than necessary.

7. How can I maintain my air conditioner?

You can maintain your air conditioner by cleaning or replacing the filter regularly, keeping the outdoor unit free of debris, and having it serviced by a professional once a year. This helps keep the system running efficiently and extends its lifespan.

8. Are there any environmental concerns with using air conditioners?

Air conditioners can contribute to climate change through their energy use and the release of refrigerants. However, newer models are becoming more energy-efficient and use less harmful refrigerants. It’s important to choose an air conditioner that is energy-efficient and has a low environmental impact.

Leave a Reply

Your email address will not be published. Required fields are marked *