Plant Window Air Conditioning System

Published Date: 02 Nov 2017

Window air conditioners are one of the most commonly used and cheapest type of air conditioners. To install one of these units, you need the space to make a slot in the wall, and there should also be some open space behind the wall.

Window air conditioners are one of the most popular types of air conditioners being used. Whether it’s your study room, bedroom, or hall, the window air conditioner can be used for almost all types of spaces.

To fit the window air conditioner in your room, you need to make a slot in one of the walls of the room that is to be cooled. This system extends around two feet beyond the wall in the back side; hence behind the wall some free space should be available so that the hot air can be thrown easily from the condenser. The dew collected from the room is also thrown from the back of the air conditioner. Thus window air conditioners can be used only if there is place available in the wall to make the slot, and there is free space behind the wall for dissipating the heat and dripping water.

Window air conditioners are comprised of components like the compressor, condenser, expansion valve or expansion coil, and the evaporator or the cooling coil, all housed in a single box. There is also a motor which has shafts on both sides. On one side of the shaft the blower is connected, which sucks hot air from the room and blows it over the cooling coil, thus cooling it and sending it to the room. On the other shaft the fan is connected, which blows the air over Freon gas passing through the condenser.

The window air conditioner is the cheapest of all air conditioning systems. If your room or office size is about less than 100 sq. ft. a window air conditioner of about 0.8 ton can be good enough. If the size of room is more than this but less than 200 sq. ft. your HVAC designer will recommend a window air conditioner of about 1 ton. For rooms of bigger sizes but less than 300 sq. ft. the system of about 1.5 ton is advisable. However, these sizes may change depending upon the number of people occupying the space, its alignment with respect to sun, and other sources of heat generation inside the room. It is better to consult your HVAC designer to find out the exact size of window air conditioner suitable for your space.

One of the complaints that window air conditioners have had is that they tend to make noise inside the room. But this problem has been greatly overcome by the present day efficient and less noisy rotary compressors, which also consume less electricity. Today a number of fancy and elegant looking models of window air conditioners are available that enhance the beauty of your rooms.

Split Air Conditioning System

Split air conditioners are used for small rooms and halls, usually in places where window air conditioners cannot be installed. However, these days many people prefer split air conditioner units even for places where window air conditioners can be fitted.

Do you have a single room but no place to make a slot for the window air conditioner? No problem, there is an excellent option in the form of a split air conditioner. The split air conditioner can be installed in rooms and offices where you don’t want to disturb the setup of the room and avoid demolitions in your favorite space. The split air conditioner takes up a very small space of your room, looks aesthetically cool and makes very little noise, ensuring sound sleep for you when you return from your day’s hard work.

There are two main parts of the split air conditioner. These are:

Outdoor unit: This unit houses important components of the air conditioner like the compressor, condenser coil and also the expansion coil or capillary tubing. This unit is installed outside the room or office space which is to be cooled. The compressor is the maximum noise making part of the air conditioner, and since in the split air conditioner, it is located outside the room, the major source of noise is eliminated. In the outdoor unit there is a fan that blows air over the condenser thus cooling the compressed Freon gas in it. This gas passes through the expansion coil and gets converted into low pressure, low temperature partial gas and partial liquid Freon fluid.

Indoor unit: It is the indoor unit that produces the cooling effect inside the room or the office. This is a beautiful looking tall unit usually white in color, though these days a number of stylish models of the indoor unit are being launched. The indoor unit houses the evaporator coil or the cooling coil, a long blower and the filter. After passing from the expansion coil, the chilled Freon fluid enters the cooling coil. The blower sucks the hot, humid and filtered air from the room and it blows it over the cooling coil. As the air passes over cooling coil its temperature reduces drastically and also loses the excess moisture. The cool and dry air enters the room and maintains comfortable conditions of around 25-27 degree Celsius as per the requirements.

The temperature inside the space can be maintained by thermostat setting. The setting should be such that comfortable conditions are maintained inside the room, and there is also chance for the compressor to trip at regular intervals. If the compressor keeps running continuously without break, its life will reduce.

These days multi-split air conditioners are also being used commonly. In units for one outdoor unit there are two indoor units which can be placed in two different rooms or at two different locations inside a large room.

Since there is long distance between the indoor and the outdoor unit, there is always loss of some cooling effect; hence for the same tonnage, split air conditioners produce somewhat less cooling effect than window air conditioners. However, with modern insulation material this gap has been reducing between the two. In any case, there are number of instances where there is just no alternative to the split air conditioners.

Packaged Air Conditioning System

The HVAC designer will suggest you this type of air conditioner if you want to cool more than two rooms or a larger space at your home or office. There are two possible arrangements with the package unit. In the first one all the components, namely the compressor, condenser (which can be air cooled or water cooled), expansion valve and evaporator are housed in a single box. The cooled air is thrown by the high capacity blower, and it flows through the ducts laid through various rooms. In the second arrangement, the compressor and condenser are housed in one casing. The compressed gas passes through individual units, comprised of the expansion valve and cooling coil, located in various rooms.

Central Air Conditioning System:

The central air conditioning system is used for cooling big buildings, houses, offices, entire hotels, gym, cinema hall, factory etc. If the whole building is to be air conditioned, HVAC engineers find that putting individual units in each of the rooms is very expensive initially as well in the long run. The central air conditioning system is comprised of a huge compressor that has the capacity to produce hundreds of tons of air conditioning. Cooling big halls, malls, huge spaces, galleries etc is usually feasible with central conditioning units only.

Available capacities of AC plant

Window type - 7000Btu, 9000Btu, 12000Btu, 18000Btu, 24000Btu

Split type - 7000Btu, 9000Btu, 12000Btu, 18000Btu, 24000 Btu, 36000Btu

Package type – 5ton, 6ton, 10ton

Central type – 100ton, 120ton, 250ton….500ton

What are the advantage and disadvantage of window and split type AC?

Window type AC

Advantages:

Cheap to buy

Relatively easy DIY installation

One self-contained, integral unit

No condensation tank to empty

No need to leave window or door slightly open

Disadvantages:

Quite noisy

Not suitable for large areas

Must be installed on an external wall

Suitable for:

This type of unit is ideal for conservatories as it can be installed through the top of the brickwork below the windows. It is also suited to installation through a sash window - simply sit it on brackets and close the window on to it. Other popular installations include portacabins, stationary caravans and small office.

Split type AC

Advantages:

Powerful outputs to cool large areas

Very quiet operation

Lots of features and functions

Attractive and unobtrusive designs

Good air distribution

Disadvantages:

Needs to be professionally installed

More expensive than portable or window units

Has a separate internal and external unit that must be joined requiring drilling and permanent fixing

Suitable for:

Lounges, bedrooms and other rooms that require quiet cooling, and any large area up to 64m2. Areas bigger than this can be accommodated with multiple units.