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Serving the greater Cherry Hill, NJ area


Low Humidity and a Furnace: Is This a Thing?

inside-gas-furnaceYou may have heard that a natural gas furnace, although one of the most powerful and reliable ways to provide heat to a home, has a major drawback—it dries out the air in a house. Since dry air during cold weather makes low temperatures feel worse, this can be a big issue. At least it is if there’s any truth to it. So … is there?

The answer is “yes and no.” A gas furnace can lead to a drop in humidity levels in a house, but the furnace doesn’t “dry out” the air itself. And not all gas furnace types have this effect. We’ll let our Cherry Hill, NJ, HVAC experts explain further.

The Atmosphere Furnace and Lower Humidity

An atmosphere furnace sounds like a piece of future space-tech. But what it refers to is the basic model of gas furnace that’s heated homes for over a hundred years until recently. What makes a furnace an atmosphere furnace is how it draws on the air it heats: it takes it from the air inside the house. The combustion chamber of this kind of furnace is exposed to the air around the furnace. If you can look inside the cabinet of your home’s furnace and see the blue light from the gas burners when the system is running, you have an atmosphere furnace.

This kind of furnace draws on the air inside the house for combustion (the burners need air in order to work). As it uses this air, it creates an air deficit inside the house, or negative pressure. When this happens, air from another location moves in to make up the deficit. This air comes from outside the house. Because air is much drier during the winter, this influx of air entering the house can lower indoor humidity. The furnace doesn’t dry the air, but it does provide an opportunity for drier air to move in.

The Sealed Combustion Furnace

The alternate to the atmosphere furnace is the sealed combustion furnace, which is a newer model of heating system. As the name implies, a sealed combustion furnace seals off the combustion chamber from the air in the house. You can’t see the flames of the burner when you look inside the furnace cabinet. The burners draw the air necessary for combustion from outside the house; a PVC tube leads from the sealed combustion chamber to an outdoor vent where it can access air.

Sealed combustion stops the furnace from creating an air deficit and lowering indoor humidity. It has other benefits as well: it prevents heat loss and lowers safety concerns. Most higher efficiency furnaces today are built with sealed combustion chambers.

The Whole-House Humidifier

If dry conditions in your home are a major problem—regardless of what type of furnace you use—you can combat it with a whole-house humidifier. You’ll need the assistance of professionals to install the humidifier, which must be integrated into the ventilation system. Call our technicians to schedule service for a humidifier or for your furnace.

Gibson Heating & Cooling serves the Greater Cherry Hill, NJ Area. Schedule outstanding service today.

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