Highly flammable creosote accumulates in all wood burning stove chimneys. This accumulation is the main purpose for sweeping a chimney at least every year before the heating season. Creosote is the combination of moisture and non-combusted gases that condense inside the chimney. As the hot gas rises inside the flue it cools and clings to the walls of the chimney. Over time, the build-up may clog the flue, causing smoke to emit from the woodstove when the fuel loading door is opened.
Make sure the fire is out in the woodstove and the flue is cold to the touch. Cleaning a hot chimney with a burning fire is extremely dangerous, as creosote will fall down the chimney and can clog the opening. The clogged opening will cause smoke to backdraught out of the woodstove.
Access the top of the chimney. Remove the chimney cap. Generally, the cap is held in place by a couple of metal screws.
Set the cap on a flat surface. Scrub the metal surfaces and the screen with a wire brush.
Install the first extension pole on the steel chimney sweeping brush. Push the brush into the flue to the end of the extension pole. Add another pole and push down. Keep adding extension poles until the sweeping brush is at the bottom of the chimney.
Pull the extension poles and the sweeping brush up and out of the chimney. Some black creosote particles will come out with the brush. Plunge the brush back inside the flue and push it to the bottom. Continue to scrub the chimney in this manner until no more particles come back up with the brush.
Remove the sweeping brush from the chimney. Shine the flashlight down the opening. Inspect the sides of the flue for remaining built-up particles. If build-up still exists, scrub the chimney.
Clean out all accumulated creosote particles from the bottom of the chimney through the lower clean-out door.
Replace the chimney cap.
Dispose of the creosote according to local disposal regulations. Do not throw the creosote back into a woodstove, as the excessive temperatures may cause an extremely hot fire. If you feel uncomfortable with accessing the roof and the chimney, contact a certified chimney sweep in your area. The chimney sweep will also thoroughly inspect the chimney for any problems.