Thermoregulation
Preparing the boiler for operation
50
GB
Equilibrage des débits en fonction de l’ouverture de la vanne de réglage Zone 2
100% = totalement ouverte 0% = totalement fermée.
0
10
20
30
40
50
60
70
80
90
100
Ouv
e
rtur
e/F
ermetur
e v
annes [%]
0
100
200
300
400
500
600
700
800
900
1000
Débit [l/h]
Débit zone 1 [l/h]
Débit primaire zone 2 [l/h]
Balancing fl ow rates based on the opening of the calibration valve Zone 2
100 % = fully open - 0 % = fully closed
Opening/closing valv
es (%)
Fl
o
w
rat
e
(l/h)
Flow rate zone 1(l/h)
Flow rate of primary circuit zone 2 (l/h)
CALIBRATION VALVE (Vm)
DIRECT CIRCUIT
FLOW RATE
MIXED CIRCUIT
PRIMARY SIDE
PARAMETER 551
CONDENSING
BOILERS
PARAMETER 551
CONVENTIONAL
BOILERS
turns closing
opening (%)
(%)
(%)
(°C)
(°C)
open
100
46
54
15
20
1
80
44
56
14
18
2
60
40
60
13
17
3
40
30
70
10
15
4
20
10
90
10
15
close
0
0
100
10
15
Troubleshooting guide
The MCD module is protected against the risk of breakdown by internal checks carried out by the PCB which, if necessary, will activate a safety
shutdown.
The table below shows the possible error codes, their descriptions and the recommended action to be taken in each case:
Error code
Description
Recommended action
7 0 1
Zone 1 heating fl ow temperature sensor fault
Check the connection of the sensor concerned.
Check the continuity of the sensor.
Replace the sensor if necessary.
7 0 2
Zone 2 heating fl ow temperature sensor fault
7 1 1
Zone 1 heating return temperature sensor fault
7 1 2
Zone 2 heating return temperature sensor fault
7 2 2
Zone 2 overheating
Check the maximum heating temperature setting for Zone 2 (para-
meter 525).
Check the connection of the safety thermostat to the "ST2" termi-
nal block on the module.
7 2 3
Zone 3 overheating
Check for the shunt and its connection to the "ST3" terminal block
on the module.
4 2 0
BUS
supply overload
A "BUS supply overload" error may appear when three or more
devices supplying power to the BUS are connected to the system.
Example: hydraulic solar pump unit, etc. To avoid
this risk, the microswitch (1) on the electronic PCB of one of the
connected devices (not the boiler) must be switched from ON to
OFF.
O
N
1
2
O
N
1
2
