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Värmebaronen Viking Bio 35
Pellet firing
Draught damper
The chimney must be fitted with a draught
damper.
The draught is affected by temperature, weather and wind.
As the combustion is affected by the draught, stable draught
conditions should be the objective. The hatch lets boiler room
air into the flue. The advantages of this are:
• more stable draught and flue gas temperature
• reduced stoppage losses
• ventilation of the flue
• drier flue gases, which reduces the risk of condensation
Smoke from the chimney
The colour of the smoke reveals the quality of combustion:
Greyish-brown: smoking combustion on account of too
little air.
Invisible:
heat shimmer. When the outdoor temperature
is above zero or down to a few degrees
below zero, the smoke must be invisible.
White:
when the outdoor temperature is lower,
only a weak white smoke of steam must
be visible.
If the boiler was previously fired with wood, the smoke
may be dark and malodorous because tar on the boiler and
chimney walls is being burned off. This may last for a week.
Efficiency
The aim is to achieve high efficiency, which means extracting
as much heat as possible from the pellets. In fact, this involves
reducing losses. The losses that should be minimised are:
Flue gas loss:
The heat in the flue gases that escape
via the chimney.
Stoppage losses:
While the burner is not operating, the
chimney draught sucks cold air through
the boiler, thus cooling it. This loss can
be reduced by means of a draught
damper.
Insulation losses:
Heat leakage via the boiler’s insulation.
A small part of this is recovered by the
combustion air being heated. In some
cases, some of it benefits the building.
The burner can be set to different power levels. It is a good
rule not to use a higher power level than is required to meet
the prevailing heat requirements.
A lower power for the burner results in a longer operating
time and lower stoppage losses, which produces higher boiler
efficiency.
The system must always have an alternative
energy source to reduce vulnerability.
Boiler tempreature control
Boiler temperature control via the burner can be used
in all operating modes. The temperature sensor must be
connected to the burner.
The temperature control controls
the boiler temperature with a
connection difference of 10 °C.
The temperature is set on the
circuit board. See 22.
When it is idle, the burner senses
a rapid decrease in temperature,
which may occur in an ‘exchanger boiler’
when hot water is drawn off. The burner then starts before
the temperature has fallen to the normal start value. The
temperature control is also suitable when the burner has
been installed in a wood-fired boiler with accumulator tanks.
If the burner is preceded by a boiler thermostat, this must
be set to its maximum value. The setting on the burner must
be 10 - 15 °C lower.
Start delay
The setting 26 allows the start to be delayed
by 0 - 135 minutes.
This function extends the burner’s operating
time, which increases its efficiency. This
function can be used with all operating modes but is
not suitable for boilers with hot water heating via a heat
exchanger.
Smoke in boiler room
If the system’s hatches and dampers are not airtight, there is
a risk of smoke entering the boiler room. A smoke detector
is a good way of discovering whether flue gases are leaking
out into the boiler room.
The boiler hatches must be closed when the burner is in
operation.
Safety
From the point of view of fire safety, it is important for the
boiler room to be clean and free of dust.
Flammable substances must not be stored in the boiler room.
The door to the boiler room must be closed.
In the event of fire or any other hazard, cut the
power to the burner and take the necessary
action.
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