1. If a black smoke from the chimney, indicating that the oxygen supply is insufficient, use the stove to carefully adjust the stacking of firewood, the firewood stack up a little bit, so that the purpose is to let the lower air more into the wood heap. If the bottom of the charcoal is too high, the ash heap of charcoal formed some, leaving more space for the flow of air.
2. If the smoke is grey, this indicates that the combustible substance is not sufficiently burned, but goes out along the flue, possibly because:
1 did not fire from above.
2 The firewood may be somewhat wet.
3 The oxygen supply is too much. It is confusing that there is a delicate balance between air and fuel, and if there is too much oxygen, the flames can hardly capture the combustible gases that fuel forms, which will produce more cigarettes.