Viessmann VITOFLEX 300-UF Operating Instructions Manual page 46

Ordering fuel
Ordering fuel
Approved woodchips
Moisture content
Moisture content
Grain size
Approved wood pellets
To EN ISO 17225-2
Quality A1
Diameter 6 mm
Substances
When buying wood for combustion, it is important to
ensure that the following foreign matter is avoided:
■ Stones
Metal particles
■
Masonry remnants
■
■ Plastics
Foreign matter would change the composition of the
fuel and therefore the critical parameters of the com-
bustion process.
Chlorine Cl
Sulphur S
Total Cl, S
Ash content, total
Alkali oxides in the ash (K
Start of ash sintering (SB)
Note
Avoid foreign matter, such as nails and iron particles,
since such foreign matter increases the wear of sys-
tem parts.
It is imperative that light metals are avoided, as these
will melt in the combustion chamber and lead to faults
in the grate area.
Notes on filling the fuel store
Danger
Risk of fire when fuel is being blown into the fuel
store. Dangerous pressure changes arise in the
combustion chamber as a result.
Switch off the heating system via the control unit
before fuel is blown in; see page 16.
46
To EN ISO 17225-4
≤ M50
≤ M35
P16S
■
P31S
■
mg/kg
mg/kg
mg/kg
g/kg
%
O and Na O) g/kg
2 2
°C
According to ÖNORM M 7133
≤ w50
≤ w35
G30
■
G50
■
Delivery methods
Wood pellets are offered in 15 to 30 kilogram sacks, in
bulk up to 1000 kilogram and loose.
Loose pellets are transported by silo tanker and blown
into the storage room via a hose system.
Observe the following limits per kg of dry fuel or dry
matter content of non-combustible constituents. The
limits for ash were determined at an analysis tempera-
ture of 815 °C. If the specifications are observed, the
minimum temperature at which ash sintering starts is
1000 °C.
Limit Comparison with natural wood
Max. 300
Max. 1000
Max. 1000
Max. 15.0
Max. 1.5
Max. 1.0
min. 1000
from forests
10
120
130
5.0
0.35
approx. 1200