As a basic answer to this very vague and un-specific question, I'd have to say, the first cave dweller who lit a warming fire in his cave. -For an answer regarding modern heating,you'd have to ask about a specific type of heating.
Virgie ammons invented the fireplace damper in September 30,1975
J. Brunander, 1926 in Portland, Oregon
To open a fireplace damper, locate the handle or lever usually located inside the fireplace or on the chimney. Pull or push the handle to open the damper fully, allowing for proper ventilation and airflow in the fireplace.
If it is a wood burning fireplace- yep.
The flue is the actual pipe or chimney where the damper is the mechanism that opens and closes the flue
In most cases, the fireplace damper is open when the chain is up and closed when the chain is down. Pulling the chain up usually opens the damper to allow smoke and gases to escape, while pulling it down closes the damper when the fireplace is not in use.
The purpose of the fireplace damper is to keep the outside elements, outside. The damper is opened only when there is a fire in the fireplace.
You close the damper when you are not using the fireplace too keep air from coming in and to keep the air from being sucked out. This is most important in the winter. You don't want cold air coming in and your heat sucked out. When you are using the fireplace you have to open the damper to allow the smoke and fumes to escape.
Shut and Open
fireplace
If you are looking for more information on where can you find info about fireplace flue damper, the best place to look is on www.csia.org/FAQs/tabid/120/Default.aspx
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