How to Improve the Draft on a Metal Chimney
- 1). Gain access to the top of the chimney with the extension ladder. Remove the top screen cap. The top screen cap is generally held in place with two screws. Clean the screen with the wire brush.
- 2). Attach the chimney brush to one of the extension poles. Push the brush into the metal chimney. Add another extension pole. Push the brush down further. Continue to add the extension poles until the brush reaches the lower portion of the metal chimney.
- 3). Pull the brush up and out of the metal chimney. Push the brush down again. Continue to scrub the interior until it is cleared of all debris.
- 4). Increase the amount of combustion air that feeds the fire. Many modern homes are airtight; this restricts the amount of air for combustion and draft in a metal chimney. Open a nearby window approximately 1 inch during operation.
- 5). Add another section of metal chimney to raise the overall height. The chimney must extend at least 3 feet above a flat roof and 2 feet above a nearby ridge that is 10 feet or closer. By raising the height, there will be fewer air currents blowing across the top of the chimney cap restricting the draft.
- 6). Check to ensure that the correct diameter of metal chimney pipe is being used. A 6-inch diameter outlet from the fire must employ at least an 8-inch diameter pipe. An 8-inch outlet must use a 10-inch diameter metal chimney for proper draft.
- 7). Burn only dry seasoned wood for optimum efficiency to the fire. Green or wet wood will burn too cool to warm up the chimney and thus create a poor draft. Cool burning fires also cause the flue to collect creosote in the chimney. Creosote buildup will cause obstructions inside the flue and lessen the draft.
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