Q&A Can 8: Flue be reduced to 6" on Colebrookdale Darby stove

Question:

I have a Colebrookdale stove

The model is a Darby with a model # 98392
This is a wood and coal burning stove.
The flue outlet is 8" diameter
I would prefer to only use wood and not coal
Can a 6" flue be used for burning wood?
Similar sized wood stove recommend a 6" flue




Answer:

No, that stove needs an 8" flue due mostly to the large door opening size. It will almost surely smoke out the doors when loading if you use a 6" flue.

As far as flue size for different fuels, it's the opposite of what you assume. Coal generally needs a smaller flue, since it does not smoke and it sends less heat up the flue. A smaller flue stays warmer and therefore is more likely to maintain a draft since coal puts less heat up the stack than wood.

Although the 6" flue can handle the BTU's of the stove, it cannot sweep such a large flue opening clear of smoke.