Herz firestar de Luxe 18, Руководство по эксплуатации

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Fuels 3
7
3 FUELS
The HERZ firestar boiler should be operated with
the fuels and their properties which are described
in this chapter.
3.1 Log wood
The HERZ
– firestar is suitable for burning logs to
operate central heating systems for closed hot
water installations. Smaller split logs enable
higher boiler performance than whole ones. We
recommend triangular firewood with side lengths
of 50 cm and edge lengths of 8 cm. Too coarse or
too long firewood may lead to reduced
performance and hollow fire. The heat value of the
wood is primarily dependent on its moisture
content. The heat value decreases with increased
moisture. The combustion of wood with high
moisture content also causes a decrease in the
degree of efficiency of the boiler.
Wood should therefore be stored for at least two
years in a dry, ventilated place. Oak needs to be
stored for about a year longer. Dry bark displays a
heat value similar to wood but there is more likely
to be increased formation of ash.
The burning of unsuitable fuels could lead to
uncontrolled combustion. The guarantee becomes
invalid! Operational faults and consequential
damage are likely to occur.
Possible consequential damage:
◼
Damage to the thermodynamic combustion
chamber, the lambda probe, the flue gas
probe due to aggressive residues in the
boiler
◼
Sooting or corrosion in the filling area due to
condensation as a result of using fuel that is
too moist.
◼
The escape of flue gas from the airflow
apertures through uncontrolled combustion
(deflagrations).
◼
Combustion time at nominal load up to
Combustion time in hours
Type FS 18 FS 20 FS 30 FS 40
Softwood
5 6,5 6 3,5
Hardwood 6 8 7 4,5
Wood
chips 3 4 3,5 2,5
3.2 Suitable fuels
The firewood must be air dried, that is, dried at
least one year with water content below 20 %
preferable half-meter logs with an average
diameter of 10 cm. If the cleavage planes of the
log wood are much larger, the log wood should be
thinner, in extreme cases 20 to 5 cm.
Small sized material may be burned only as
admixture. From the smaller material may be
added less. Wood briquette with 6 to 10 cm
diameter according EN 17225-3.
Only one oversized log each boiler filling
To split a root stock to such thin pieces is very
hard work. Per boiler filling maximum one large
root stock piece are burned up in the stack.
Type of
wood
Calorific values (by wood
moisture 25%) in kWh/stere
Beech 1890
Oak 1930
Pine 1520
Spruce 1330
We recommend to use beech
wood. Do not mix different types
of wood. The use of one type of
wood promotes a consistent
burn-off and reduces burning
disturbance. However, if it cannot
be avoided to use different types
of wood, the boiler must be filled
in
layers (softwood below,
hardwood above).
3.3 Not suitable fuels
When burning wet fuel with more than 30% water
content, condensation water formation and
corrosion on the walls of the filling chamber occur.