Sime MURELLE HM, Manual

Page: 107 / 120

107
ES
PT
ENG
3.4 EXTERNAL SENSOR (fig. 13)
If there is an external sensor, the heating
settings SET can be taken from the climatic
curves according to the external tempera-
ture and, in any case, limited to with the
range values described in point 3.3 (para-
meters PAR 22 for zone 1, PAR 25 for zone
2 and PAR 28 for zone 3). The climatic
curve to be set can be selected from a value
of 3 and 40 (at step 1). Increasing the stee-
pness of the curves of fig. 13 will increase
the output temperature as the external
temperature decreases.
3.5 CARD FUNCTIONING
The electronic card has the following func-
tions:
– Antifreeze protection of the heating
and sanitary water circuits (ICE).
– Ignition and flame detection system.
– Control panel setting for the power and
the gas for boiler functioning.
– Anti-block for the pump which is fed for
a few seconds after 24 hours of inacti-
vity.
– Antifreeze protection for boilers with
an accumulation boiling unit.
– Chimney sweep function which can be
activated from the control panel.
– Temperature which can be shifted with
the external sensor connected.
It can be set from the control panel and
is active on the heating systems of both
circuit 1, circuit 2 and circuit 3.
– Management of 3 independent heating
circuit systems.
– Automatic regulation of the ignition
power and maximum heating.
Adjustments are managed automati-
cally by the electronic card to guaran-
tee maximum flexibility in use of the
system.
– Interface with the following electronic
systems: climatic regulator CR 53,
remote control CR 73, thermal regula-
tor RVS, connected to a management
card of a mixed zone ZONA MIX code
8092234, card solar INSOL code
8092235 and to board RS-485 for
managing up to 8 boilers in cascade or
implement a communication type
Modbus (slave RTU-RS485, Reference
Guide PI-MBUS-300 Rev. J) cod.
8092243.
NOTE: If using CR 53 set parameter
10 to 2 (PAR 10 = 2).
3.6 TEMPERATURE
DETECTION SENSOR
Table 4 shows the resistance values of the
heating, DHW and exhaust fumes thermi-
stors
.
If the C.H. flow sensor (SM), C.H. return
sensor (SR) and the exhaust fumes sen-
sor (SF) is faulty or open circuit, the boi-
ler will not function on either heating or
DHW. If the D.H.W. sensor (SS) is faulty
or open cir cuit, the boiler will work
without modulation to the D.H.W. tempe-
rature.
3.7 ELECTRONIC IGNITION
Ignition and flame detection is controlled
by a single electrode on the burner which
guarantees reaction in the case of acci-
dental extinction or lack of gas within one
second.
3.7.1 Functioning cycle
Burner ignition occurs within max. 10
seconds after the opening of the gas
valve. Ignition failure with consequent acti-
vation of block can be due to:
– Lack of gas
The ignition electrode persists in
discharging for max. 10 seconds. If the
burner does not ignite, the anomaly is
signalled.
This can happen the first time the boi-
ler is switched on after a long period of
inactivity due to the presence of air in
the gas pipes
It can be caused by a closed gas tap or
by a broken valve coil (the interruption
does not allow for opening).
– The electrode does not discharge.
In the boiler, only the opening of the gas
to the burner can be detected. After
10 seconds the anomaly is signalled. It
can be caused by an interruption in the
electrode wire or if it is incorrectly
anchored to the connection points. Or
the electrode may be earthed or stron-
gly worn: it must be replaced.
Or the electronic card may be defecti-
ve.
– No flame detected
After start-up the electrode continues
to discharge even when the burner is
on. After 10 seconds, the discharge
stops, the burner is switched off and a
fault is generated.
This fault is sometimes caused by the
shorting of the electrode cable or by its
improper fixing to the connection
points. The electrode is connected to
the earth or badly worn and must be
TABLE 4 (SM - SR - SF - SS sensors)
Temperature (°C) Resistance (
Ω
)
20 12.090
30 8.313
40 5.828
50 4.161
60 3.021
70 2.229
80 1.669
Fig. 13
ATTENTION: curves are calculated at an ambient temperature of
20°C. The user can act on the boiler controls to change the envi-
ronment set for which the bend has been calculated by ±5°C.