Sometimes, the quickest way to cool off during the summer is via a fan. Sure, air conditioners are lovely, but to be effective, you must run them for a while to get that comfortable temperature. However, while ACs cool indoor temperature, what’s interesting is that even the best fans technically don’t lower the temperature of a room. This fact leaves many wondering, “how do fans work?”

KEY TAKEAWAYS:

  • Fans work using a motor that rotates a set of fan blades, which circulate the air.
  • While fans produce a cooling effect via evaporation, they don’t lower a room’s temperature.
  • A fan’s power is measured by how many cubic feet of air it can move per minute, which takes into account the power of the fan’s motor and the diameter of the fan blades.

And for anyone with a fan that isn’t working correctly, we have a great article explaining how to fix a fan that won’t spin.

How Does a Fan Move Air?

Fans aren’t wizardry. Humans first harnessed wind power thousands of years ago, and modern electric fans are only one of the most recent developments, although not quite as recent as you might think. The first electric fan ran on a DC current and was invented in 1886 by Dr. Schuyler Wheeler.

Insider Tip

Remember to keep noise levels in mind when choosing a fan. In smaller rooms, the noise of a fan motor will be much more noticeable.

The basic science behind cooling with fans is this: Humans generate body heat, and bodies generate sweat to create a healthy body temperature (known as thermoregulation). So, air flowing across sweaty skin creates evaporation, which produces a cooling effect on the body.

Regarding how they work mechanically, it’s relatively simple. In an electric fan, an electric motor rotates a set of fan blades, creating air circulation. So, while fans don’t lower a room’s temperature, they do reduce body temperature through the power of evaporation. In fact, fans raise a room’s temperature slightly due to the heat radiated by the electric motor, but you’d never know it.

Choosing a Fan

The scientific processes aside, it’s important to know how to purchase a fan that will create a suitable cooling effect for your particular space.

Fan power is calculated by how much air they move; the technical term for this is CFM (cubic feet per minute). CFM is determined by the motor’s power (speed) and the diameter of the fan blades.

Finding an exact CFM isn’t vital for most house fans, like box or tower fans, so it’s okay to select one without worrying about it. But for ceiling fans and larger industrial fans, this matters because CFM helps determine how often the air in a room is replaced by outside air, which can be necessary for meeting safety requirements. And, for those looking for additional ceiling fan resources, you can check out our article that shows you how to control a ceiling fan’s speed.

Warning

A running fan accomplishes nothing but wasted electricity. Therefore, ensure your fans are off if no one is occupying the room.

While fans are still widely used, the technology has evolved in recent decades. If you want to learn more about this, you can find our article explaining how bladeless fans work.

STAT: The average full-sized keyboard has 104 keys. (source)

How Do Fans Work FAQs?

Do fans work the same way on dogs?

Unlike humans, dogs sweat through their paws, not their bodies, and pant to cool down. Because of this, fans only provide comfort to canines when the temperature is below 80 degrees Fahrenheit. And even then, the fan will only cool their coat, though that does help them dissipate body heat.

Are bladeless fans better than regular fans?

Bladeless fans optimize the airflow through the use of physics. As a result, they increase the airflow's effectiveness while cutting energy costs.

Which type of fan is best for keeping cool?

Usually, a direct fan, like a box or standing fan, is best for creating a cooling effect. Electric ceiling fans are used more to cycle air rather than to cool.
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