Diy Secondary Burn Wood Stove . Wood stove with secondary burn theory and application, part 1. Diy secondary combustion / air. Huge Homemade stove retrofitted with a Secondary Air System (pictures from www.hearth.com Diy secondary combustion / air. 2, the secondary air you are looking for will only work well if you burn dry wood. The secondary burn will allow the stove to have a burning efficiency rate of at least 80 percent.