We all know that ceiling fans help to make a room feel cooler when blowing at you on a hot day.People even use ceiling fans in outdoor areas. The movement of air is essential when it comes to assisting people in keeping comfortable. How ceiling fans work, however, is something that goes unnoticed.
The Basics of Heating and Cooling
Most people remember from school that heat rises. When a ceiling fan is introduced to a room and turned on, the hot air that is trapped above the fan is pulled downward through the blades, and it creates an indoor breeze. This is called a downward draft as the warm air is moving in the opposite direction than it normally would.
After the downdraft happens, the hot and cool air begin to change places; hot air continues to try to rise as cool air attempts to move under the hot air. This causes the air to circulate. The longer the fan is on, the greater the circulation. This is how a room begins to feel cooler.
Do Fans Actually Cool Down a Room?
No, ceiling fans do not change the temperature in a room. However, they do help you to feel cooler. When a downdraft is created, and the cool air is exchanging places with the warm air, the room will feel cooler. It’s not that the temperature in the room has changed; what has happened is that the air moves around faster, giving the illusion of cooling.
The only way that a fan will cool down a room is if the fan is pulling cooler air into the room from a place that is dramatically cooler. For example, if you have an air conditioner on in one room and turn the fan on in another, the room with the fan will exchange cooler air with the room that has the warmer air. A temperature change can eventually occur.
What Does Reversing the Direction on a Fan Do?
There is a reverse button on most fans. The function of the reverse changes the direction of the fan blades and changes the flow of hot and cold air. Instead of pulling hot air up and pushing cool air down, it does the opposite. This means that when you change the fan to reverse, it pushes the warm air to the bottom and the cool air to the top. In other words, it pulls the cool air up and keeps it there, due to the rotation of the blades.
Again, the actual temperature in the room doesn’t change. However, the illusion of warming the room takes place due to warm downward air circulation.
How Can a Fan Help Keep Energy Costs Low?
Whether you are trying to keep your home cooler in the summer or warmer in the winter, a fan can be a great asset to keep costs low. By continually keeping the air circulating, the house can heat or cool the air correctly and evenly. Eventually, all the air will be at the same temperature, and this will reduce your heating or cooling costs.
Why are There Different Speeds on a Fan?
Different speeds give you control of how fast the air can circulate around the room. If you have the ceiling fan on low, it will take considerably longer to make a complete cycle and feel a breeze. However, if the fan is on high, the air will move faster and cause the downdraft effect to take place quickly.
This quick downdraft effect can make the room feel considerably cooler in a shorter span of time.
The science behind ceiling fans if pretty straight forward. Using basic air conversion, the advent of the ceiling fan significantly superseded the scientific reasoning behind its creation.