NBE RTB PHOENIX v16.0, Manual

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BOILER ROOM DESIGN:
The internal diameter of the chimney must be sufficient enough for the amount of flue gasses the chimney has to lead away. If the internal
diameter is too small, this will prevent the smoke from exiting fast enough due to the large resistance in the chimney. This could cause the
smoke to turn back; thus allowing for toxic fumes to enter into the house. Simultaneously, the pellet fuel may not be completely burned, due
to the lack of oxygen for combustion. This can cause traces of tar like soot to sit in the chimney and create what is called creosote, which
increases the risk of chimney fire.
The chimney opening must also not be too large since cold air can enter the chimney from the top. When the chimney becomes cooled,
condensation can occur and develop soot inside the chimney. Soot is mostly a cosmetic problem, because it can penetrate through the
chimney and cause ugly brown splotches to appear on the walls inside the house.
In addition, it is important that the chimney protrudes high enough above the roof so the smoke does not bother the surrounding houses.
Environmental authorities have the possibility of prosecution if there are neighbors that complain about the smoke or odor.
What are the common signs that the chimney is not
working?
- Smoke in the hopper.
- Warm drop shaft.
- Smoke billows out of the fan or boiler during start-up.
- Power is reduced due to lack of underpressure
If you have any problems with your chimney, it is a good idea to keep
a ”diary” of any draft problem; as draft problems are often associated
with wind in certain directions.
Wind blowing on one side of the house can cause under pressure on
the other side of the house.
Overpressure and under pressure will try to balance out – even
through a chimney if possible. It is a good idea to ask your chimney
sweeper about the size of the chimney and flues, the location of
chimney cleaning doors, and whether it is required to have steps on
the roof. He will also perform a fire prevention inspection.
6. Air
The pellet boiler should be able to get enough air for combustion. This
can be achieved if the pellet boiler is installed in a room which is
equipped with a sliding window with an adjustment bracket, an
adjustable air vent from the outside, or by providing combustion
chamber air through a duct from the outside. The area amount of the
fresh air valve should generally be the same as the internal diameter
of the chimney. It should also be mounted on the same side as the
chimney to compensate for any pressure differences.
Note
: Drum dryers, range hoods, or oil burner in the same room all
use high pressure blowers that can steal the air in the room and cause
under pressure in the boiler room.
7. Water tap
There must be a tap in the boiler room.
If the boiler output is less than 60 kW, a powder extinguisher is
sufficient (at least 5 kg).
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