Smoke Chamber – The smoke chamber in a fireplace services the purpose of gently compressing combustion byproducts into the chimney while not causing any backdraft. A sloping wall is usually the part of sound fireplace design which accomplishes this.
Chimney Damper – Within your chimney are doors which are lever- or pulley-activated. You use this part of your fireplace to close it off when it’s not in use. The chimney damper is also effective at helping to prevent water from entering your home. And if you don’t have screens on your chimney cap or if the screens have been damaged, the damper can help to prevent birds and animals from coming into your home when the fireplace isn’t being used.
Smoke Shelf – Just behind the chimney damper is a smoke shelf which serves several functions. It catches both rain water and falling debris, and it helps with the effective transition of large amounts of smoke entering into the small space in your chimney.