If you have a wood-burning fireplace with a masonry chimney, consider installing a top-sealing damper. Traditional dampers can leak up to $200 a year in heating and cooling costs through the chimney flue. Top-sealing dampers mount on the chimney top and completely seal the flue when the fireplace is not in use, preventing up to 90 percent of chimney-related energy loss. These unique dampers are spring-loaded to facilitate a tight seal and operate using a pull-chain mechanism that hangs down from the damper into the fireplace box. Top-sealing dampers not only save money in heating and cooling costs, they also prevent animal and insect infestation, weather-related damage and annoying down draft odors that plague most chimneys.

Top-sealing dampers are available through your local chimney specialist. Although best when installed by a professional, top-sealing dampers can be installed by homeowners willing to follow the manufacturer’s instructions.

Step 1: Make sure the flue liner is dry and clean and the chimney top is free of any damaged or loose materials.

Step 2: Liberally apply the manufacturer-provided damper adhesive to the top of the chimney flue. Be careful not to get the adhesive on anything other than the chimney flue. Direct contact with the adhesive can cause severe skin and eye irritation.

Step 3: Install the top-sealing damper with the highest side of it facing the direction that most prevailing winds come from. Before pressing the damper into place, be certain that the operating spring or chain mechanism will hang freely once the damper is installed.

Step 4: Lower the operating mechanism into the chimney and press the damper into place. Allow the damper to set for 24 hours before using the fireplace.

Step 5: Use a masonry drill bit and a power drill to properly mount the cable bracket to the inside of the fireplace wall.

Step 6: Once the bracket has been installed, slip the operating cable through the bracket and pull the cable until a slight tension can be felt.

Step 7: Install the cable handle and hook the cable to the bracket. The tension of the cable will keep the top-sealing damper closed.

Step 8: Return to the chimney top to confirm that the damper is tightly sealed. Make any adjustments from ground level and start saving those energy costs that have been escaping through the chimney.