Herz pelletfire, Operating Instructions Manual

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3 Fuels
8 Betriebsanleitung_pelletfire_Touch_Englisch_V1.2
3 FUELS
The HERZ pelletfire
– boiler should be operated
with the fuels and their properties which are
described in this chapter.
3.1 Wood chips
The HERZ
– pelletfire 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 50cm and edge lengths of 8cm. 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
Woodchips 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 10cm. Are the cleavage planes of the
log much longer, according to the log should be
thinner, in extreme cases 20 to 5cm.
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 14961-3.
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/ster
Beech 1890
Oak 1930
Pine 1520
Spruce 1330
We recommend the use of beech
wood. Do not mix different types
of wood. The use of one type of
wood promotes a consistent burn-
off. 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.
Furthermore should not be burned:
Garbage, plastics, paper and cardboard (only for
starting the fire) sanding dust, wood shavings,
wood chips smaller than thumb-size, coal and
coke, the respective Clean Air Act (state law)
usually prohibited fuels such as old railroad ties,
plastics, particle board, impregnated wood...