Air-conditioners guzzle the most energy in the home. So, if you want to keep the electricity bills down, does this mean you should do without one, and brave the humidity and heat? Not really. The most energy-efficient air-conditioner available today is the inverter system. Inverter systems control the speed of the compressor motor to allow a continuously regulated temperature when switched on. This means the air from the air-con is cool, and yet it consumes the least amount of energy possible.

Here are three things to note before you purchase your air-conditioning system:


Consider what type of air-conditioning system you need. The following list will educate you on the four general types of air-conditioning systems.

i) Window unit: Contrary to the name, window units aren’t mounted on window frames; window units are the ones mounted below windows.

ii) Casement unit: These are the units that are actually mounted onto window frames. They are commonly found in apartments as they don’t require a separate condenser, much like window units. However, both of these air-conditioning systems are quite energy-inefficient.

iii) Cassette: It’s likely that you’ll have one of these above your office ceiling boards. These distribute cool air evenly and at a greater volume, necessary for sizeable spaces such as offices and some larger homes.

iv) Split-system: A split-system is where the hot(compressor) and cold“ (fan coil units) sides are separated – or split, as the name suggests, unlike window or casement units. The split-system is perhaps the most efficient system for apartments and small offices.



How big a unit would cool your home? It all depends on which room you are talking about, and how cool you want that room to be. Some simple calculations will help you to determine the capacity of air-conditioning you require. First, find the approximate volume of the room you wish to cool, then multiply that number (in cubic feet) by 25, and that would be about the capacity you require for your air-conditioning unit.

The capacity is important because if your unit is too small, it has to run at a higher output for a longer period of time. If it’s too large, the air reaches the set temperature quickly enough but the humidity isn’t removed, which affects how “cool“ we feel in the enclosed space.



Whether you hire a technician or you would rather do it yourself, make sure you clean and replace the air-conditioner filters. If the filters are dirty, airflow would drop, and the system will not perform at its optimum, which means, you may reach for the controller to lower the temperature. 

If you’re using an air-conditioning system that is over five years old, and isn’t an inverter system, you should consider switching to a new model, even if you’ve maintained it religiously. Changing from a non-inverter split system to an inverter version means more energy savings and up to 30 per cent off your cooling bill.