Secondary Combustion Chamber; Fire-Tube Hydronic Boiler - Max-Ox MX-900B Operator's Manual

serves to manually adjust and set the Tertiary combustion air flow rate
into the Secondary Combustion Chamber upper combustion air inlets.

Secondary Combustion Chamber:

All of the hot gases rising off of the burning surface of the fuel rise
upward into a well-insulated but extremely hot ceramic-lined secondary
combustion chamber. Carefully proportioned and highly preheated
secondary combustion air is introduced into the rising flammable fuel
gases within the secondary combustion chamber in such a way as to
promote thorough mixing with the rising fuel gasses. The resultant
mixture produces very high combustion temperatures, and therefore
very complete combustion.

Fire-Tube Hydronic Boiler:

All of the very high temperature fully combusted gasses continue to
flow upward into a modern, high efficiency, 2-pass hydronic heat
exchanger, wherein all of the available heat energy is extracted, without
permitting water vapor in the flue gas to condense. Heat energy is
transferred to circulating water for your hydronic space heating or
industrial /commercial process hot water needs.
Heat Exchangers and Water Vapor: The Hot Water Heating Boiler
system flue gas exhaust temperature and the boiler return temperature
are automatically controlled so as to prevent condensation of water
vapor within the heat exchanger. This means that just enough heat
energy deliberately remains in the exhaust gases so that the water vapor
does not cool down to the point where liquid water forms within the
heat exchangers, or your chimney. Instead, the water remains in the
vapor state, and is exhausted into the atmosphere. On cool days you
will see this water vapor form a vapor cloud plume as the exhaust rises
up into the atmosphere.
Max-Ox™ MX-900B Operators Manual, Rev. 0
Page 20 of 54