This popular fireplace fail is easily diagnosed. If your fire smokes, has very little draw, or is generally "sluggish", but picks up as soon as you open a door or window.....you need to provide more air! Insufficient air supply has been the second most common reason for fireplaces smoking in my experience. You need to ensure your fireplace has an adequate supply of air both for combustion, and to replace the air that's always leaving the house via the flue.
