You may have heard it stated as a solid, unshakeable fact that a gas furnace dries out the air in a house. All that winter static electricity, cracked skin, and eye-and-nose irritation comes from the furnace sucking the moisture out of the home’s air.
But is this true? When you stop to think about how a gas furnace runs, it might not make much sense that it would remove moisture from the air. After all, there’s no water dripping in the furnace the way water drips in an air conditioner, which does remove moisture from the air as it runs. Is the “dry air from a furnace” a myth?
The answer is “yes and no.” A gas furnace can contribute to drier conditions, although not exactly the way you think. And there are ways you can deal with this problem, either with an IAQ solution or a different furnace in Colorado Springs, CO.
The Gas Furnace and Dry Air
The way a gas furnace heats air is by combusting natural gas and gathering this heated gas inside a metal chamber called the heat exchanger. The walls of the exchanger turn hot, and the air pushed through the furnace and into the ventilation system picks up the heat from the exterior surface of the exchanger. This process does not change the amount of moisture in the air.
The reason a gas furnace may cause a drop in indoor humidity is that it draws on the air in the house to combust natural gas. Combustion requires oxygen, and in a standard furnace this oxygen comes from the air around the heater. This standard furnace is also called an atmosphere furnace: it draws air through a grill to mix with the combustion gas. If you can look into your furnace and see the blue light of the flames, it’s an atmosphere furnace.
Because an atmosphere furnace uses indoor air for combustion, it creates an air deficit inside the house. This negative air pressure causes air from outside the house to push indoors—and because this is winter air, it’s drier than the indoor air. The influx of outside air causes humidity levels to drop. And there you have it: drier air thanks to the furnace.
Combating This Problem
There are several ways you can fix dry air trouble in your house because of a gas furnace. You could switch to an electric furnace, which doesn’t combust gas and therefore won’t draw on air in the house. But gas furnaces are more effective heating systems and cost less to run, so you probably want to stick with a gas furnace.
One option is to have a whole-house humidifier installed. Our technicians can put a humidifier into the ventilation system so it raises the humidity level around the house. You can control the humidity from a control panel (a humidistat) to keep it balanced—you don’t want too much humidity.
Another option is to have a sealed combustion furnace installed. This is a type of gas furnace that has its combustion chamber sealed from the house so it doesn’t draw on indoor air. Instead, it pulls air from outside through a PVC pipe. This type of furnace provides great heating without the worry of drier air.
Regardless of what you need for the best winter comfort and health, you can trust our team to deliver results.
Contact Peak Home Performance today to schedule an appointment with our technicians.