A fireplace damper, or chimney damper, seals off the chimney flue while it is not in use and keeps the cool or warm air generated by your HVAC unit inside your house. It is a metal spring door placed at the top of the chimney with an extended metal chain that permits you to open and close the chimney from the fireplace. Chimney dampers come in several designs and can be installed just above your fireplace or at the top of the chimney by way of a chimney damper cap.
Chimney dampers serve several purposes within a chimney; the most important one being energy conservation. However, dampers can also help keep animals, like possums and birds, from getting into your home through the chimney flue. It also prevents insects, like blowflies and wasps, from entering the chimney during the warm summer months. If critters do make it into your chimney, a chimney damper installed just above the fireplace can serve as a barrier between that animal and your home.
Chimney dampers also stop rainwater and debris from entering your home through the chimney.
If you are unsure about whether or not you need a damper for your particular chimney, please contact a professional at 877-669-4669 for expert advice. Not all fireplaces have the same needs.