Running your aircon together with your fan can be a quick and efficient way to cool the room while saving energy. With the additional support of a fan to keep the cool air circulated around the room, this will help to reduce the burden on the aircon system which results in energy savings. Generally, turning both the aircon and the fan on at the same time works well – but there are certain methods and tips to create greater efficiency with just your fan or aircon that will be discussed below.

 How does running an aircon and a fan together save energy?

It is common knowledge that a fan consumes significantly less energy than an aircon, but since both are electrical appliances, doesn’t that mean that running both at the same time consumes even more energy? The rationale of saving energy when using both appliances is simple: The aircon’s job is to create cold air but may not be very efficient in circulating the cold air. The issue with air is that it tends to settle rather than circulate on it own. With the help of an external fan to support the circulation of air within the room, the process of cooling the room becomes much quicker and thereby reducing the load on the aircon. Now that you understand how the energy-saving process comes about, here are some tips to be more efficient with your fan and aircon:


Point your fan head downwards: Hot air rises and cold air sinks. With this principle, the cold air from your aircon will sink down closer to the ground. Bypointing your fan toward the ground, you are effectively circulating the cool air that has settled on the ground, upward to cool more parts of the room.


Position the fan beside/under the aircon vent: This will help to circulate the coldest air, fresh from the aircon, to further parts of the room.


Increase your aircon’s temperature: If you have been using your air-conditioner without a fan, then you can try increasing your aircon temperature in intervals of 2 degrees while using a fan to find a comfortable temperature that suits you with the additional air chill factor from the fan. Generally, the optimal aircon temperature for comfort is at 25 degrees Celsius.


Turn on the fan first, then the aircon: Most rooms are built to be well insulated so that the cool air will not escape easily. Unfortunately, this works for hot air as well – when the aircon is turned off, hot air may accumulate in your room and get trapped inside. Before turning on your aircon, open your doors and windows and turn on your fan for 10-15 minutes first to help dispel the hot air. Once all the hot air is out, you can close the windows/doors and turn on your aircon – your room will cool much faster this way.




Frequently asked: Why does it feel not as cold when both the aircon and fan are running together?

If you usually spend time directly under the aircon, then you might realize that it might not feel as cold when both the aircon and fan are running together. One of the main reasons is due to the increased circulation in the air. The mix between the cold and hot air in the room becomes more consistent, which results in a longer duration for the space directly under the aircon to turn cool. However, if you are located away from the aircon (i.e the other corner of the room), then the time taken for the air to be cooled would be shorter for you. Therefore, the usage of a fan is more preferably if you want more even cooling throughout the room as opposed to in one spot under the aircon only.


Another possible reason is that the temperature set on the thermostat of the air-con is close to the ambient temperature. With the air-chill factor coming from the support of the fan, the set temperature is easily achieved and the aircon does not need to ‘work’ as hard to achieve the desired temperature, and thus reducing its dehumidifying effect.  Lower levels of humidity in the air contribute to a more comfortable environment as our bodies are able to transpire better.


How the body perceives comfort is a mix of factors such as humidity, temperature, and air velocity in the room. We must keep in mind that the air-conditioner is more inclined towards temperature control with limitations on humidity and air velocity, and therefore the additional support from a fan will help in the air velocity factor to generate more comfort for you.

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