eta PelletsCompact PC33, Руководство по установке

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Information for installation Chimney
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If the diameter is too large, the chimney will not be
heated sufficiently, and the exit velocity and
temperature will be too low. The flue gas then lacks the
energy to rise and, in extreme cases, the smoke can
sink down along the roof.
Chimneys with a diameter more than 50% greater than
needed must be renovated to reduce the diameter. If a
chimney is designed for use with two simultaneously
operating boilers, it may prove to be oversized for the
partial load from only one boiler. If there really is only
one chimney available, a buffer storage tank can help
avoid an overly small partial load.
DANGER!
Do not connect fan-assisted boilers and wood-
burning stoves to the same chimney
Although not expressly prohibited, connecting a fan-
assisted boiler and a wood-burning stove to the same
chimney is a dangerous combination. For every wood-
burning stove has an air intake. When the chimney is
cold, any fan-assisted boiler, whether it burns oil or
wood, will blow flue gas through this opening into the
living area. If the wood-burning stove's firebox door is
not closed and the boiler is defective at the same time,
acute carbon monoxide poisoning is even possible.
Wood-burning stoves require a considerably larger
chimney diameter, which cannot be heated by the fan-
assisted boiler. Cold flue gas does not rise from the
opening; it sinks and can reach living quarters through
open windows. Moreover, it may be possible to hear
the boiler's fan in the living quarters through the wood-
burning stove.
DANGER!
Do not connect fan-assisted boilers and gas
boilers to the same chimney
Most gas-fired boilers do not have a sealed air flap,
and if the fan-assisted boiler is started when the
chimney is cold, the flue gas is pushed through the gas
boiler into the boiler room. This is not greatly helped by
a flue gas damper in the flue pipe of the gas boiler, as
these dampers are not certain to seal well on closing.
In the case of atmospheric gas boilers, old fireclay
chimneys only stay dry due to the gas boiler's overflow
opening. The water from the flue gas condenses in the
chimney. During heating pauses, air flows through the
overflow opening and dries the chimney. If this air flow
is blocked by a flue gas damper, the moisture can
destroy an old fireclay chimney.
Obsolete regulations stipulate the wrong chimney
Laws and regulations demand a moisture-resistant
flue system for oil and gas and one that is resistant to
soot fires for solid fuels.
Wood is a solid fuel. However, in the lower output
range, the temperature of the flue gas can be below
100?, and condensates can be deposited in the
chimney. The chimney must therefore be moisture-
resistant, "contrary to regulations". Builders making a
chimney resistant to soot fires in compliance with the
law must then look on helplessly as the condensate
destroys the chimney wall.
Soot fires are possible in natural-draught boilers or
wood-burning stoves regulated by throttling the air
supply. When the wood fire is at full intensity and the
boiler temperature has been reached, a thermostat
closes the air flap. This stops combustion. However, as
the combustion chamber temperature doesn't fall, the
wood continues to gasify. Unburned wood gas
condenses to tar in the chimney, which can be ignited
by sparks from the fire.
With modern, lambda-controlled wood boilers, soot
fires of this kind are virtually impossible, as the control
system restricts wood gasification, not the air. In mod-
ern,lambda-controlled wood boilers, the control
system shuts down the fire by stopping the fuel supply,
without closing off the supply of air to the fire. This way,
there is no lack of air and no flammable tar in the
chimney. In addition, the low flue gas temperatures of
modern wood boilers also provide no ignition source
for a soot fire. Modern and properly maintained wood
boilers therefore pose no danger to chimneys from
soot fires.
Moisture-resistant W3G flue systems
Since 2005, W3G chimneys (classified according to
the German DIN 18160) exist that are resistant to both
moisture and soot fires. These chimneys are approved
for all fuels. Most of these W3G chimneys have
ceramic inner pipes, which have a significantly longer
service life than metal chimneys due to their acid
resistance.
Flue pipe to chimney preferably stainless steel
Due to the low flue gas temperatures, we recommend
that the flue gas pipe from the boiler to the chimney is
made of a stainless steel flue duct that is not sensitive
to moisture.
Provide a short, ascending flue pipe to the
chimney
The flue pipe from the boiler to the chimney must be
short, leakproof and ascending. "Attractive" right-angle
flue offsets with two or more bends are bad in a flue