Sime Dewy 30 Guia Del Usuario página 96

– "Modureg Sel." connector (14 fig. 17)
The bridge must always be fitted in order
for the boiler to function.
ATTENTION: It is essential that the opera-
tions described above be carried out by
authorized technical staff.
3.2 TEMPERATURE SENSOR
AND WATER PRESSURE
TRANSDUCER
Tables 3 - 3/a show the resistance values
(Ω) that are obtained on the sensor as the
temperature varies and the transducer
values obtained as the pressure varies.
When sensor (SM) is int errupt ed,
neither of the boiler's heating services
will function. With D.H.W. sensor (SB)
interrupted, the boiler will only work in
heating mode.
TABLE 3 (Sensors)
Temperature (°C) Resistance (Ω)
20
30
40
50
60
70
80
TABLE 3/a (Transducer)
Pressure Resistance (Ω)
(bar) min
0 297
0,5 260
1 222
1,5 195
2 167
2,5 137
3 108
3,5
3.3 ELECTRONIC IGNITION
Ignition and flame detection is controlled by
two electrodes located on the burner.
These guarantee maximum safety with
intervention times, for accidental switching
off or gas failure, of within one second.
3.3. 1 Operating cycle
Rotate the selector knob to summer or win-
ter, and verify that green led (
confirm the presence of voltage.
The burner must be ignited within 10
seconds. However, it is possible for ignition
failures to occur, with consequent activa-
tion of signal indicating that the control box
has "locked out".
– FGas failure
The control box runs through the cycle
normally sending electric power to the
ignition electrode. The electrode conti-
92
nues spark discharge for a maximum of
10 sec.If the burner does not light, the
lock-out indicator will light up.
This may occur upon first ignition or
after long periods of boiler lay-off when
there is air in the pipes. It may be caused
by the gas cock being closed or by one of
the valve coils having a break in the win-
ding, so that the valve cannot open.
– Ignition electrode fails to spark
In the boiler, only the gas to the burner
is seen to open. After 10 sec. the war-
ning light indicating equipment "lock-
out" lights up.
This may be due to a break in the wire of
the electrode or to the wire not properly
fastened to the electric terminal of the
control box;
– No detection of flame
The continuous spark discharge of the
electrode is noted starting from ignition
even though the burner is lit.
12.090
Af t er 10 seconds have elapsed, the
8.313
sparks cease, the burner goes out, and
5.828
the warning light indicating equipment
4. 1 61
"lock-out" lights up.
3.021
2.229
There could have a break in the wire of
1.669
the sensing electrode or the electrode
itself is touching earth: the electrode is
worn out and needs replacing. The con-
trol box is defective.
max
When there is a sudden voltage failure, the
320
269
228
200
173
143
113
90 94
) lights up to
600
500
400
300
200
100
0
200 400 600
burner shuts out immediately; when power
supply returns, the boiler will start up again
automatically.
3.4 FLOW SWITCH
SAFETY VALVE
A flow switch safety valve (17 fig. 3) interve-
nes, blocking the operation of the burner if
the boiler is without water due to the for-
mation of an air lock in the heat exchanger
or if the circulator is not working.
NOTE: If replacing the flow switch valve,
make sure that the arrow stamped on the
valve points in the same direction as the
flow of water.
3.5 SYSTEM
AVAILABLE HEAD
The head available for the heating plant is
shown as a function of the flow in graph in
fig. 18.
3.6 MAINS ELECTRICITY
CONNECTION
Use a separate electricity supply to con-
nect the room stats and relative zone val-
ves or pumps.
The micro or relay contact connection is
made to TA-CR-SE (J2) connector of the cir-
cuit board after having removed the jum-
per (fig. 19).
con by-pass
senza by-pass
800 1000 1200 1400
PORTATA (l/h)
FLOW RATE (l/h)
1600
Fig. 18