Heatmor 400-4S, User Manual

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CHAPTER 13
FIREBOX AND OTHER COMPONENTS
Firebox
Principles of the Firebox
Wood is burned inside the firebox to generate heat. This heat is absorbed into the water
in the water jacket. The firebox and water jacket are one welded component and can be
replaced. When the water is up to temperature and the combustion air blowers are off, the
firebox must be airtight.
Operation of the Firebox
Temperatures within the firebox can reach 2000 degrees Fahrenheit. Smoke exits from the
firebox into the flue. During normal operation, there will be a slight buildup
of black creosote on the firebox walls. This buildup will sometimes appear flaky.
Maintenance / Result
Wood should not be thrown into the firebox in a rough manner. Creosote should never
have to be scraped off the firebox walls.
Secondary Air Wing
Principles of the Secondary Air Wing
As wood is burned inside the firebox the location of the wood changes. The secondary air wing allows air to
enter the firebox in the right location in relation to the wood for a cleaner and hotter burn.
Operation of the Secondary Air Wing
The secondary air wing works on a hinge design with a cable and pulley system to the handle to the front of
the furnace. If the secondary air wing will not release when the handle is released, it may be stuck and can
be released with a push or a pull to it, do not touch the secondary air wing directly, poke it with a long metal
handle. Do not drop the secondary air wing roughly, it could disturb the wood or the fire below. Wood should
be loaded towards the front of the firebox so that the secondary air wing can move correctly.
Maintenance / Result
Wood should not be loaded above the secondary air wing. The tips of the
secondary air wing may deform but should not affect the main function of the
design.
Removal and Replacement
1) Remove all wood and let the unit cool down.
2) Disconnect main power.
3) Disconnect the back of the secondary air wing from the
cable/pulley system.
4) Remove the secondary air wing from the top of the airbox by lifting
it out. Replace the secondary air wing with a new one.
5) Reverse the above.
Firebox (secondary air
wing in down position)
Secondary Air Wing Handle (to the
left of the firebox door)