Editor’s Note: This post was provided by one of our paid sponsors, Chimneyballoon. Stop heat and AC from escaping through your fireplace or woodburner chimney with a Chimney Balloon fireplace plug draft stopper.
On a cold winter evening, who of us is not tempted to go to the living room, stoke up a fire in the fireplace, and read a book in front of the hearth? You may be thinking “I am doing myself a favor by supplementing the furnace with additional heat”. But there’s a dark secret about your fireplace: you are making your house colder, and could be contributing significantly to pollution depending upon how you burn. Fireplaces can be monstrous energy eaters!
The wood burning fireplace is an “Energy Eater”
The air action that a wood-burning fireplace initiates in our home is wasteful. The second the damper is opened, heated air begins pouring out of the top of the chimney. As the fire in the hearth accelerates, the combustion process grabs already-heated air from your home and burns the oxygen and combustible gasses in it. The heat that is created in this combustion quickly rises and grabs more heated inside air and tosses it up the chimney. You can restrict the amount of inside air that the fireplace has access to by installing glass doors, but this will also severely limit the amount of radiant heat that fireplace can cast forward into your living space. This radiant heat is the heat you feel on your skin in front of the fireplace, and is the only usable heat that the fireplace will produce since the combustion heat is pouring out the top of the chimney. In the meantime the home is drawing in cold outside air from other places (i.e. windows, light sockets, doors, etc) to replace the air that is escaping the home through the chimney. This is referred to as the “stack effect.”
Losing heat even while dormant
Even while the wood fireplace is not being used, the traditional metal dampers tend to leak air since they warp and degrade rapidly in the extreme heat and corrosive soot environment. There is a removable and reusable chimney plug available in assorted sizes called a Chimney Balloon fireplace damper that inflates into place in the flue and seals it off efficiently to stop fireplace odor, heat loss and the cold chimney draft.
The good, the bad, and the pollution
If you burn a fast hot fire, this creates very little smoke and pollution, and it can give you a noticeable amount of radiant heat gain in the room the fireplace it is in. However, this fire is also using huge amounts of your heated inside air for it combustion which exceeds your heat gain ratio. A slower fire is even worse since you are still losing heated air out the chimney, getting very little radiant heat in return, and generating black sooty smoke. This black type of fireplace smoke is a terrible pollutant and contributes to respiratory irritant for people with asthma and allergies.
Wood burning fireplaces are wonderful nostalgic centerpieces for many American homes. But a homeowner should be aware of the issues associated with fireplace use and keep them from being an energy eater.
For more information, and one potential solution to this problem, see ChimneyBalloon.