High efficiency solid fuel burning stove

Abstract

A solid fuel heating apparatus including a secondary combustion chamber in gaseous communication with a primary combustion chamber for increasing heating efficiency and for reducing polluting emissions. The secondary combustion chamber is lined with a refractory material. The entrance to the secondary combustion chamber is disposed at the bottom thereof adjacent the grate, and the grate containing the fuel is sloped at an acute angle with respect to the vertical to cause charcoal to accumulate adjacent to the orifice and to cover the entrance orifice of the secondary combustion chamber. Exhaust gases drawn into the secondary combustion chamber must first pass through the charcoal so that they are preheated prior to being mixed with secondary air. Means are provided for metering secondary air into the entrance orifice to cause mixing of the secondary air with the exhaust gases when the exhaust gases are at their maximum temperature. Refractory baffles are disposed within the secondary combustion chamber to enhance mixing of the combustion gases and to reradiate heat into the combustion gases. The baffles are vertically aligned at the bottom to reduce flow restrictions but still cause significant mixing, and are curved at the top to focus the gases into a choke zone. The side walls of the stove are insulated to contain heat within the primary combustion chamber.