1. Air Conditioner Size Not Suitable for Room Area

Many people think that the bigger the air conditioner, the higher the capacity, and the faster it cools. However, in reality, an air conditioner that is too large for the room cannot distribute cool air evenly or may reduce humidity excessively.

Before buying an air conditioner, calculate the appropriate cooling capacity for your room to save electricity monthly and make your room cooler, more elegant, and refined.

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2. Keeping Doors Completely Closed While Using the Air Conditioner

Few realize that the air inside a closed room with an air conditioner is 2 to 5 times more harmful than outdoor air. While it's important to limit opening and closing the door to prevent cool air from escaping, don’t let the room become too stuffy as this harms your health.

Every 15-30 minutes, open the door for a few seconds to let the room "breathe" and exchange air with outside. Choose air conditioners with air filtering and antibacterial functions to keep indoor air fresh, or equip a ventilation fan to bring outdoor air in, making the indoor environment more comfortable.

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3. Installing the Air Conditioner in the Wrong Position

The installation location greatly affects the energy efficiency of the air conditioner. Many homes place the unit on the hottest wall in the room, making the machine work harder to cool the overheated wall before cooling the air.

Therefore, install the air conditioner in a shaded corner so the room temperature drops quickly, then gradually cool the surrounding walls. This helps the room cool faster and stay cool longer.

Also, do not block the air conditioner with plants or furniture. Lastly, ensure the unit is far from heat sources like lamps or other equipment.

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4. Running the Air Conditioner 24/7

During hot days, many families run the air conditioner all day long. However, this wastes electricity and seriously harms health from staying in a closed, air-conditioned room for too long. You should not stay in the air-conditioned room for more than 2 hours continuously.

When sleeping, your body can tolerate higher temperatures than when awake. Also, since the body moves less during sleep and is more vulnerable to cold, adjust the air conditioner temperature higher at night. When leaving the room, open the door wide and stand at the doorway for a few minutes to help your body adjust to the new air.

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5. Setting the Temperature Too Low

This is a common mistake because many households think lowering the temperature will cool the room faster and better. However, this can cause thermal shock and harm your health.

Turning on the air conditioner at too low a temperature can cause colds due to the large temperature difference between inside and outside. Do not enter the air-conditioned room immediately after coming in from the sun or intense exercise when sweating a lot. Before leaving the room, stand at the open door for a few minutes to let your body adjust to the hot outside air.

Limit frequent in-and-out movement to reduce body stress from constantly adapting to temperature changes. Especially for the elderly and children with weaker immune systems, this can cause headaches, sore throats, and nasal congestion. Usually, the best air conditioner temperature is around 25°C (77°F).

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6. Not Using a Fan

Many people think that air conditioning replaces the need for a traditional fan. However, in reality, fans help the air conditioner work more efficiently by circulating air around the room. This tip not only saves money on your electricity bill but also reduces wear and tear on the machine.

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7. Turning Off the Air Conditioner with the Remote Control

Air conditioners consume a lot of electricity, but many people don’t realize that the device still consumes a significant amount of power even when turned off by the remote control. This happens because turning off via remote puts the device in standby mode, making it easy to restart but still consuming electricity roughly equal to a light bulb.

Therefore, if you don’t want to waste extra money monthly, make sure to turn off the air conditioner’s power at the source completely. This also helps maintain the device’s durability and extends its lifespan when the power supply is stable.