If you find yourself complaining that parts of your home are too hot in the summer and too cold in the winter, there’s a good chance you’re not using your furnace dampers correctly. Here’s how to balance your HVAC system for year round comfort.
What’s a Damper?
Most people are familiar with the registers and vents you see in the actual rooms (and with the concept of closing a vent in a particular room to slow or stop the flow of air through the heating and cooling system into that room). But closing the vents in rooms is nowhere near the most efficient way to control the flow of air through the system.
That’s where balancing dampers come into play. A balancing damper is just a simple mechanism inside the ductwork that closes off a given duct—they are called balancing dampers because you use them to balance the flow of air throughout the system. Below you can see an example of a manual balancing damper.
Unlike a register (which is located at the end of the duct run where the ducting meets the floor, wall, or ceiling of a room), however, the damper is located very close to the central unit. The benefit of this arrangement is that it closes down the duct closer to the source of the hot or cold air and helps more efficiently redirect the forced air somewhere else in your home.
So what does that mean in practical terms for you? It means more cold air from the AC in the summer, and more hot air from the furnace in the winter directed precisely where you want it.
Practically speaking, adjusting your dampers is as simple as turning the lever to open or close the damper. There’s a wee bit more to it than just that, however, especially if you’ve never done it before—so let’s dig into some practical tips and tricks. We’ll assume you’ve never fiddled with your dampers and will walk you through the entire process start to finish.
Locating Your Dampers
First thing’s first. You can’t adjust anything until you find your dampers. This should be pretty straight forward for most folks, but there will be some situations for some readers in which adjusting the dampers isn’t an option.
In some homes (especially newer construction) there aren’t balancing dampers attached to the ductwork—a rather poor cost-cutting measure in our opinion. In other homes, the dampers, if they exist, have been covered up by drywall during remodeling projects or when a basement was finished into a rec room or some such thing. (Conscientious contractors will often use “false” vents to provide access to the damper handles, so shine a flashlight in all the ceiling vents in your finished basement to check if what you thought was a functional vent is actually an access panel).
On the opposite (and more positive) side of things, if you have a premium system in place, you might have electronic dampers that are automatically controlled by your heating and cooling system and provide zone-controlled air flow. But let’s be real here—if you have this system, you’re probably not reading this article because your automatic system is already taking care of things. If you’re not sure whether you have such a system, you can figure it out pretty easily; instead of physical handles, your dampers will have little motors with wires attached.