A very good friend, an HVAC technician, taught me something new the other day—something that seems obvious when you think about it, but which wouldn’t have occurred to me if he hadn’t mentioned it.
The humble ceiling fan, as most of us already know, reduces perceived temperature in a room by circulating air.
The faster that air moves across the skin, and the faster it works to evaporate perspiration on the surface of the skin, the cooler the air seems to be to someone sitting under or near the fan. What I didn’t realize is that ceiling fans are remarkably effective at distributing warm air more evenly throughout a room—especially a room that is just in the process of warming up and which still feels slightly chilly. Because ceiling fans are so linked in most of our minds with summer—and especially with perpetually humid climates in the southern United States and other parts of the world—it isn’t immediately obvious to most of us that ceiling fans can be useful at other times of the year. Because hot air rises, ceiling fans are dynamite at making sure that at least some of the warm, stratified air moves away from the ceiling area and toward the floor. It never would have occurred to me to switch my ceiling fan on to help me warm up a cold room on a frigid day. However, the fact that fans can be helpful in winter is an important reminder that a large number of HVAC systems and technologies are inherently multi-purpose, and, with some tweaking, can usually be extremely helpful in a variety of contexts and situations.