The chimney is the engine of the wood burning stove. If your chimney does not fit your wood burning stove (too short or poorly insulated), you will experience a bad chimney draught which will cause troubles when you light a fire which will result in smoke in your living room, a poor combustion and a heavy smoke development which will bother your neighbors.

You can check the draft in your chimney with this simple test:

• Open the door slightly (5-10 mm to allow air passage) and light up a lighter next to the side of the door. 
• If the flame is drawn towards the combustion chamber, the draft is sufficient.
• If the flame is vertical or is pushed towards the outside of the stove, the draft is insufficient or wind blows down in the chimney.

Warning: please only perform this test with a cold stove.

See second 1:01 - 1:17 in the film below