Fireplace flue open or closed. See a diagram of the parts of a chimney here when the damper is closed it slows the loss of heat that would otherwise go up the chimney. No way to adjust the thing. If there is a burst of cold air the flue is open.
Ceiling to floor metal fireplaces have a metal latch located on either side of the fireplace that allows for easy testing of the flue. Adjusting the damper allows you to burn a fire efficiently and safely. A fireplace damper is a little metal flap that sits inside your flue.
When you convert a wood burning fireplace to gas you get to choose the style of your new gas logs and the pattern of the flame. This duct within your chimney includes a damper that can be opened or closed by a lever or pull chains in most instances. Now some fireplace including some masonry and some prefab types you can adjust the damper during the burning of a fire.
The flue is essentially a channel inside the chimney the smoke is funneled through and its controlled by the damper a pair of small steel doors. Air can flow both ways so outside air can come into your home and the heated air from your home can escape through an open damper. The easiest way to tell if the fireplace flue is open is by placing a hand into a cooled fireplace and feeling for cold air.
It blocks off the air flow when its closed and lets air in when its open. Historically the term flue meant the chimney itself. First though you choose whether to buy logs that require a vent for the gas byproducts or logs that allow you to burn them without a vent.
A flue is a duct pipe or opening in a chimney for conveying exhaust gases from a fireplace furnace water heater boiler or generator to the outdoors. A throat damper is a metal door located above the firebox but below the flue pipe.