Cleaning your flue pipe is essential for several reasons. The debris that can build up in a flue pipe can be potentially hazardous and flammable. When you allow too much debris to collect on a flue pipe, you are also restricting the amount of air that can pass through the chimney. This will reduce the ability to have roaring fires in the fireplace, and it will also reduce the efficiency of your furnace. You should have your flue pipe cleaned at least once every two years by a trained professional chimney sweep. If you use a fireplace all year round, then you should get that flue pipe cleaned once a year.