a stove comprises a fire - box , and an ash - chamber separated by a grate . air intake means is provided beneath the ash - chamber . air supply means connected to the air intake means extends vertically past the ash - chamber and the fire - box to an upper region of the fire - box . air delivery means provides communication between the air supply means and the fire - box . in use fuel burning inside the fire - box causes external air to be drawn into the air intake means , through the air supply means and through the air delivery means to a region above fuel in the fire - box . external air is pre - heated by passing underneath the ash - chamber and past the ash - chamber and the fire - box during its passage into the fire - box . turbulence caused by an interaction between pre - heated air entering the fire - box and heated air already present causes smoky combusted air to be pushed away from a dose at the front of the fire - box .