PROPER HEATING WITH WOOD …

Wood is stored solar energy. An optimum air supply is the decisive factor for ensuring the best combustion in the heating chamber. There are three types of air supply:
a) PRIMARY AIR, this is delivered from below through the riddle grate and should only be used when burning coal,
b) SECONDARY AIR, the main combustion air which is delivered to the wood gas flame through the lower glass-door rear air supply duct,
c) TERTIARY AIR, delivered to the tips of the flames as preheated, post-combustion air through the upper glass-door rear air supply duct.
An inadequate air supply or an excessively high water content of the wood fuel may lead to poor, sooty combustion (smoldering).