Chances are that you have one or more ceiling fans in your home. These fans, which were invented in the early 20th century, are mostly used to cool down the occupants of a room by moving air around. The blades, which are set to run counterclockwise in the summer, move air so that it brushes against the skin as perspiration evaporates, leaving a cooling effect.
Some of these fans have reverse switches that allow you to run the blades clockwise. This is done in the winter to push the warm air from the furnace down to floor level.
How Efficient Are Ceiling Fans?
Long-bladed fans installed in the ceiling are often marketed as energy efficient, meaning they help save money on electricity use by making a home’s occupants feel cooler or warmer. The fact is, ceiling fans do use some energy, and the motor can give off some heat, so you only save money when you cut back on energy use at the thermostat. Furthermore, it’s crucial to not leave the fan running when you leave a room. These fans don’t cool themselves. They only help us feel cooler or warmer, but they do not raise or lower the temperature in and of themselves.
It’s also important to check out their efficacy rating before you buy. Efficacy is the measure of efficiency. It is determined by measuring the output (or airflow) vs. electrical energy use. A good efficacy rating would be 100 cubic feet per minute (cfm) of airflow per watt of electrical power. A poor efficacy rating would be 30 cfm.
Some other facts about these fans:
- Long-bladed fans do a better job of moving air than short-bladed ones.
- It’s better to run these fans on low or medium speeds than on high speeds. They are less efficient at moving air, so you feel cooler or warmer if you select high speeds.
- Keep the blades clean. Dirt on the edges will slow down the blades and cause them to drag.
For more on ceiling fans or if you have any other questions regarding HVAC, contact Mowery Heating, Cooling and Plumbing, serving greater Indianapolis for more than 50 years.