- Nov 27, 2012
- 0
Question:
One more question: I had a serious downdraft problem with my new woodstove and had a special cap put on the chimney to help prevent this. The chimney is porcelain on the inside and stainless steel from the roof up.From the top of the stove to the top of the chimney pipe it's probably about 20 feet tall. The problem I now have is that when I start a fire (with fatwood) smoke pours back into the room thru the air intake vents of my Jotul 8. I think this is because the chimney is cold - as a matter of fact, when I open the door to the stove I can feel cold air in it. I think the problem is that until the cold air in the pipe is displaced, it's heavier than the warm air and forces it out thru the stove. Once the stove starts to heat up I get a good draft going but I need to know if there's anything I can do prior to that to prevent the blow back into the room. Thanks for any thoughts you have on this.
Answer:
This is a typical "flow reversal" that occurs when the stove is not in use. There is a lot of discussion about this in the chimney essay at https://www.hearth.com/what/specific.html and in the Q and A section of HearthNet.
Basically, you want to start the draft up - with a small sheet of paper placed as high in the stove as possible, before starting. After that the stove should work fine. In really bad situations, a tee may be installed on the stovepipe (hard with porcelain pipe) and paper can then be inserted directly into the pipe and lit.
One more question: I had a serious downdraft problem with my new woodstove and had a special cap put on the chimney to help prevent this. The chimney is porcelain on the inside and stainless steel from the roof up.From the top of the stove to the top of the chimney pipe it's probably about 20 feet tall. The problem I now have is that when I start a fire (with fatwood) smoke pours back into the room thru the air intake vents of my Jotul 8. I think this is because the chimney is cold - as a matter of fact, when I open the door to the stove I can feel cold air in it. I think the problem is that until the cold air in the pipe is displaced, it's heavier than the warm air and forces it out thru the stove. Once the stove starts to heat up I get a good draft going but I need to know if there's anything I can do prior to that to prevent the blow back into the room. Thanks for any thoughts you have on this.
Answer:
This is a typical "flow reversal" that occurs when the stove is not in use. There is a lot of discussion about this in the chimney essay at https://www.hearth.com/what/specific.html and in the Q and A section of HearthNet.
Basically, you want to start the draft up - with a small sheet of paper placed as high in the stove as possible, before starting. After that the stove should work fine. In really bad situations, a tee may be installed on the stovepipe (hard with porcelain pipe) and paper can then be inserted directly into the pipe and lit.
