NBE V7, Руководство пользователя, Страница: 7 / 29

Boiler Room Design
The size of the chimney opening must match the amount of flue gases the chimney has to lead away.
If the opening in the chimney 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 soot to sit in the chimney and create what is
called shining soot, 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 prosecuting you if
there are neighbors that complain about the smoke or odor.
What signs are there, if the chimney is not working?
• Light sensor is sooty or melted.
• Smoke in the hopper.
• Warm drop shaft.
• Smoke billows out of the fan or boiler during startup.
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 supplied with 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 the combustion chamber with air through a duct
from the outside. The area size 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: that drum dryers, range hoods, oil burner in the same room, all use high pressure blowers,
that steal the air in the 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(at least 5 kg) will suffice.