Q: The Chimney Balloon website says that it can save a homeowner up to 30% on the home heat. How do you get this figure?
A: The 30% savings is if you have no damper on your fireplace or if the damper is stuck open. The Department of Energy estimates a home with no damper on the fireplace will increase its heating bill 30%. The DOE website mentions the Chimney Balloon in an indirect way on the website as an “inflatable stopper” See this link here: http://www.eere.energy.gov/consumer/your_home/space_heating_cooling/index.cfm/mytopic=12570
Below is the quote from the DOE website:
“Flues are ideal for leaking heat and warm air out of your home. If you have a fireplace that you don’t use, plug and seal the flue. If you use the fireplace, be sure to close the flue when the fireplace is not in use. You could also use an inflatable stopper, available commercially, to temporarily seal the chimney and avoid air leakage through the flue.”
The above quote is Copyright property of the US Department of Energy.
Your heat savings will be less than 30% if you do have a functioning damper, but even the best of metal dampers are often only 75% efficient since they have no insulation and they conduct cold. Most used metal dampers are less than 50% efficient due to warping and corrosion.