If you can see up into the flue, the damper is open. Keep the damper open until all open flames are gone. The Stupid Fireplace Damper Is Stuck Or Missing And Your Heating Dollars Are Going Up The Chimney When It Is Not Bein Fireplace Damper House Heating Fireplace Make sure the damper is working properly with tips from a li. How to work a fireplace damper . A gas insert requires a venting system and an electric insert requires neither a vent nor a damper. A pivot damper operates on a long, jointed handle. Damper controls are usually located near the top of the firebox. How does a fire damper work? You can look up into the chimney and see it open and close. Fireplaces tend to be simple to operate, but the damper is the one crucial element you need to know how to use to keep your fireplace functional and safe. When working a fireplace damper, be sure to use pliers or an oven mitt in case the metal is hot. When you aren’t using your fireplace, it prevents drafts and ...