21
7.7 Regulation of the feeding screw fuel
A
screw potentiometer
regulates the amount of fuel (
fig 7.4
). It is already set on a value
corresponding to the power of heat generator model, see
tab.7.7
below.
Small fuel regulation are allowed through the
screw potentiometer
using a screwdriver.
The fuel amount increases turning it clockwise, it decreases when turned anticlockwise.
The fuel conveying capacity, measurable in mc/h or kg/h, depends on the apparent mass
density of the fuel and the number of turns of the screw; reference is made to the wood
pellet having a lower heating value (l.h.v.) of 17.6 MJ/Kg (4.9 KWh/Kg) as from prospec-
tus 8 of standard EN303-5 for the fuel of test “C”, approximate dimensions Ø6 x 25mm
and an apparent mass density between 600 and 660 kg/mc.
CAUTION !!
Do not, under any circumstance, exceed the maximum adjustment values
l.h.v. of 4.9 kWh/kg.
In case of using solid fuels different from the fuel of reference (wood pellet) without certifi-
cation, we recommend checking its l.h.v. in order to guarantee optimal performances. In
case the fuel has l.h.v. different from that of reference (wood pellet),
tab. 7.7
will be mere-
ly indicative. Various attempts must be made to obtain an optimal regulation by carrying
out the above-described operations.
7.8 Switch-off
To switch off the boiler the main switch has to be on “0” position. The switch off will be
automatic if the fuel ends completely in the firebox.
FUEL REGULATION
min Hz
max Hz
mod.CS SMALL 20
12
15
mod.CS SMALL 30
15
18
mod.CS SMALL 40
23
25
mod.CS SMALL 60
30
35
mod.CS SMALL 80
40
45
mod.CS SMALL 100
50
55
fig. 7.4
Tab. 7.7
