A flue is simply any pipe or tube that draws smoke and gases out of the home through a safe channel, like a chimney or vent. For example, if you use a fireplace, the smoke from the fire is drawn through the chimney flue and out of your home. Without this safe channel, the smoke and gases would accumulate inside your home, creating an extremely dangerous environment.
The damper, or flue damper, is a small device inside of the flue. It serves a few purposes, including regulation of air flow and protection against rain and pests. A properly functioning damper is essential to any flue.
While a simple damper merely covers the flue and allows air to pass, a barometric flue damper specifically regulates the amount of heat loss through a furnace or a fireplace and can help to maintain ideal temperatures by preventing heat loss. This can increase the energy efficiency of a home and reduce annual fuel costs by about 5 percent, according to the U.S. Department of Energy.
If you notice smoke or excessive heat in your home while your furnace is running or you have a fire in your stove or fireplace, you may have a poorly functioning damper. If the damper is stuck or broken, it will not maintain the proper air flow and may cause a blockage within the flue. This poses the danger of smoke inhalation and carbon monoxide exposure. Have your flue inspected every year to prevent such problems.