Heatmor 200X - Stages of Combustion

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approach ideal and result in proper combustion. Your HEATMOR™ furnace is designed to
create this situation. Wood too high in moisture content results in lower temperatures and
unreliable performance.
Stages of Combustion
During the four stages of combustion, wood breaks down into water, smoke and charcoal.
The rst stage occurs when wood is placed in the furnace. It must be heated to drive off
the moisture. The higher the moisture content, the greater the amount of heat needed and
subsequently lost for heating purposes. The drier the wood, the more rapidly it can be heat-
ed and passed through this rst stage of heating the water. When moisture is being driven
from the wood, white smoke may be emitted from the chimney. This is what we call “steam
smoke”. It is mostly water vapor.
In the second stage, at 500 degrees Fahrenheit, wood begins to break down chemically. If
this smoke is released but not burned, two-thirds of the energy in the wood will be lost. A
hot re is needed to burn the smoke.
The third stage takes place at temperatures above 1,100 degrees Fahrenheit. At this point,
the smoke is burning at 100 percent efciency, as long as the proper amounts of oxygen,
temperature and draft are present. If one of these elements is missing, the combustion
will be incomplete. The third stage is the most important stage of wood combustion since
smoke represents two-thirds of the wood heat.
The fourth stage takes place after 1,100 degrees Fahrenheit to 2,000 degrees Fahrenheit
temperatures have been reached. The smoke and gases are completely burned and the
charcoal remains, which represents approximately one-third of the wood heat, and allows
the re to re-start when required.
When a new charge of wood is loaded, the rst stage of combustion begins again. The
charcoal heats the fresh wood until it gets hot enough to react and ignite, and the process
continues. All four stages can take place concurrently but complete combustion requires
proper placement of secondary air and adequate temperatures. This is incorporated in the
design of the HEATMOR™ furnace.