Generally, two main types of room air conditioners are used. They are
- Window air conditioner and
- Split air conditioner.
The details of the working of these air conditioners are discussed below:
1. Window Air Conditioner:
The most common air conditioner used for tiny houses and offices is a window air conditioner, as shown in Figure 1. It is a cubical unit, a complete conditioning system in itself; it requires a window, or such space, where it can be installed with its face inside the room, and the exterior part outside the room, as it discharges heat outside. It is effortless to install. As the compressor and evaporator both are in one unit, its cooling capacity is limited; this makes it suitable only for small places. The main components of a window AC are Compressor, Expansion valve, Hot condenser coil (exterior), Cold evaporator coil (interior) Two fans Control units.
Figure 1: Window Air Conditioner and its components
Front Panel
The front panel is part of the window unit, which the user sees inside the room. It has a user interface controlled either manually or through remote control. The older the team usually is of mechanical control type with rotary knobs to control the temperature and fan speed of the air conditioner. The newer units come with electronic control system where the functions are controlled using remote control and touch panel with digital display. The front panel has adjustable horizontal and vertical louvers to adjust the airflow direction as per the user’s desire. The fresh intake of air called VENT (ventilation) is provided at the panel if the user wants to have a certain amount of fresh air from the outside.
Indoor Side Components:
The inside parts include:
- Cooling Coil with an air filter mounted on it. The cooling coil is where the heat exchange occurs between the refrigerant and the air in the room.
- Fan Blower is a centrifugal evaporator blower to discharge the cool air to the room.
- Capillary Tube is used as an expansion device. It can be noisy while operating if installed too close to the evaporator.
- Operation Panel is used to control the temperature and the speed of the blower fan. A thermostat is used to sense the return air temperature and another one to monitor the coil’s temperature.
- Filter Drier is used to removing the moisture from the refrigerant.
- A drain pan collects the water that condensates from the cooling coil and is discharged outdoors by gravity.
Outdoor Side Components
The outdoor side parts include:
- The compressor is used to compress the refrigerant.
- A condenser Coil is used to reject heat from the refrigerant to the outside air.
- A propeller fan is used in the air-cooled condenser to help move the air molecules over the surface of the condensing coil.
- Fan Motor is located here. It has a double shaft where the indoor blower and outdoor propeller fan connect.
2. Split Air Conditioner:
The split air conditioner comprises two parts: the outdoor and indoor units (Figure 2).
- The outdoor team consists of components like the compressor, condenser and expansion valve fitted outside the room.
- The indoor unit consists of the evaporator or cooling coil and the cooling fan fitted inside the room.
Split units have aesthetic looks and add to the beauty of the room. The split air conditioner can be used to cool one or two rooms.
Figure 2: Split Air Conditioner and its Working Line Diagram
Since the compressor and condenser unit can be installed outside the room, inside the air conditioner feels calm and quiet. Split AC is an excellent option for office use and large commercial buildings. Due to its compact size, split AC is becoming popular even for household usage.
3. Difference Between Split and Window ACs
The working principle of both window AC and split AC is the same, but they have different capacities; both are used for other places. Split AC, being divided into two parts, has a large degree, so it’s ideal for use in large offices and big rooms in the house. On the other hand, window AC is one unit conditioner, so it’s suitable for small rooms only. Window AC creates noise, whereas the Split unit is calm. Window AC is more undersized in size as compared to split AC. Window AC is easy to install, but in the case of split AC, the exterior unit is to be connected to the interior unit through rubber tubes, which might cause trouble. Moreover, a window is necessary if you want to install window AC in your room, but for split AC, the interior unit will be connected to the compressor unit through a small hole in the wall.
