No Draw

  • Type of Stove?

    Different types of woodstoves have different needs as far as draw is concerned.  Old fashioned stoves which were not designed to be as efficient as newer models would generally work well even with a weaker draw, newer technology brought on by increased demand by the environmental protection agency to produce cleaner burning woodstoves, as well as the demand for more efficient use of wood fuel have brought about the development of units which will burn wood with a high output while giving a longer burn time and lesser emissions produced.  These units require a stronger draw as the features that make the unit burn more efficiently create resistance to the pull of the chimney.

  • Type of Chimney?

    The type of chimney used can have some bearing on what to look for when draw is not present. The two types of chimneys used would be a masonry (brick) chimney, and the premanufactured (pipe) chimney.  The masonry chimneys usually have ""clean out"" doors at the bottom of the flue. This door would not effect function of older type stoves as they do not create the resistance mentioned above, but the newer type stoves do so and what happens is the chimney (which will pull from the path of least resistance) will start to pull air through that clean out door as well as any other air leaks in the flue or the stovepipe.  This reduces the amount of air pulled through the stove itself, causing the fire to die when the door to the stove is closed. The premanufactured kit chimney in some configurations will have a ""clean out Tee"" if the chimney is run through the wall and up, the cap at the bottom of this tee should have an airtight seal as well.  Another common problem when using a premanufactured chimney concerns the installation, if the chimney is not installed with sufficient height as well as the proper 10/2 Rule, (see above) the flue will not generate enough draw to operate the unit.

  • Outside Air?

    Houses these days are generally built to hold heat much better than in years past.  This is obviously a good thing as it lowers the cost of heating and cooling, however the less drafty a structure is, the harder it is for a chimney to pull air from it.  This condition is known as ""Negative Pressure"" essentially when a home is under negative pressure, the unit will burn only when the door is cracked open as there is no resistance to draw, air can be pulled more easily through the doorway of the unit straight up the flue.  To correct this problem, attaching an air intake from outside of the structure for the chimney to pull its air through will take house pressure out of play as the air pressure would be the same coming in the intake as it is going out the chimney.

  • Location in the home.

    Air inside of a house behaves similarly to how it does in a chimney.  Warm air rises and cooler air descends.  As this air is warmed and rises it becomes trapped in the upper portions of the home. This actually causes the air pressure inside the house to be higher close to the roof than it is in the lower parts of the house, especially in the basement, which means that the draw of the chimney has to work harder to pull air out of the mild vacuum that is present in basements. this also means that the higher in the house the stove is located in (upper floors) draw would be stronger as the inside air pressure would be slightly higher than the outside pressure.

  • How New is House?

  • How is Stove Being Operated?