
8
STNS3E ed 09/08 NIKE Star 24 3 E
Technical documentationTechnical documentation
e circuit is composed of an atmospheric burner and a mo-
dulating gas valve, which respectively allow the combustion
of the gas and the adjustment of its ow rate.
Operating.
e electric power supply of the main coils (3) causes the
opening of both internal shutters of the valve, thus allowing
the passage of gas towards the burner. e outlet ow rate/
pressure is then adjusted by acting on the gas valve stabiliser
by means of the modulation coil (1).
e fuel is injected, by means of the burner nozzles (6), into
the horizontal Venturi pipes (ramps). Here, an optimal air-gas
mixture is obtained that is ignited by the spark of the ignition
electrode (4).
Modulating gas valve (VK 4105 M).
e gas valve is equipped with two main coils (3) and a mo-
dulation coil (1) controlled by the integrated P.C.B.
e maximum and minimum outlet pressure values are cali-
brated on the valve (see gas adjustments).
Main electric coils (3).
ey are two ON-OFF coils that are powered (230 V AC) by
the integrated P.C.B. when burner ignition is necessary.
ey are connected in series and powered at network voltage
rectied by means of a diodes jumper (U1) positioned inside
connector (2) (see wiring diagram).
Gas circuit.
Modulation coil (1).
It is a low voltage coil that is controlled by the integrated
P.C.B.
It acts on the gas valve stabiliser and allows the variation of
the outlet pressure proportionally to the direct current that
passes through it.
Modulating gas valve (SIT 845).
e gas valve is equipped with two main coils (3) and a mo-
dulation coil (1) controlled by the integrated P.C.B.
e maximum and minimum outlet pressure values are cali-
brated on the valve (see gas adjustments).
Main electric coils (3).
ey are two ON-OFF coils that are powered (230 V AC) by
the integrated P.C.B. when burner ignition is necessary.
ey are connected electrically in parallel and powered from
the mains voltage via a relevant connector (2).
Modulation coil (1).
It is a low voltage coil that is controlled by the integrated.
COIL POWER SUPPLY RESISTANCE
EV1 + EV2 230 V AC EV1 = 2,85 kΩ
EV2 = 1,35 kΩ
Modulation coil
(Blue)
250mA DC (G20)
320mA DC (L.P.G.) 28 Ω
Reference values with boiler at maximum power
Connector viewed
from the gas valve
Modulation
Coil
Modulation
Coil
Connector viewed
from the gas valve
EV1
EV2
Common