It's important that an indoor fireplace flue damper be opened before igniting anything in a fireplace. The damper looks similar to a trap door and is located at the bottom of the chimney. When it's open, it provides an opening for smoke from the fireplace to escape. If it is closed while a fire is lit, smoke will enter the room rather than leave via the chimney with possible deadly consequences. If nothing is burning in the fireplace, keep the flue damper closed. This saves money on energy by preventing heat or air conditioning loss up through the chimney.
When the fireplace is not in use, it allows the opening to the chimney to be closed. This can help keep heat in the house, and birds and squirrels out.
The flue is the actual pipe or chimney where the damper is the mechanism that opens and closes the flue
fireplace
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FIREPLACE
the flue should be opened
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.
When the fire is burning, until the ashes are cold. The damper should be open at these times.
Yes, there are automatic fireplace flue dampers available for sale on the internet. Check out www.fluesentinel.com and www.actionair.co.uk or fireplace showrooms near you for more detailed information.
When there is a fire in the fireplace, the flue should be all the way open. Otherwise, some smoke and unhealthful gases will come out into the room. The damper should be all the way closed to keep out wind or cold air when there is no fire in the fireplace.
Then you have a shortage of combustion air, and it is drawing air down the unused fireplace flue. Close the damper of the unused fireplace, and check for exhaust fans that may be drawing air out of the house.
the flue is the part of the fireplace that goes from the firebox to the outside of the building.
By flue, I believe you mean the damper in the chimney, which has the effect of closing off the flue. Close the damper any time you are not using the fireplace. Remember -heat rises -so heated air will also rise up and out the flue in the winter. In the summer it is also good to keep the flue closed because heat and humidity will activate the smelly properties of the ash and creosote in the firepalce chimney and create a bad odor in the home. In order for a damper to do its job it must seal tightly/ If your existing mechanical damper is broken, missing or in a bad state you can repair it or replace it with a chimney top damper or a chimney balloon. But, open the damper before lighting a a fire, or it will rapidly get quite smokey in the house.