40
P
N
L1
1 2
A8
3 4
5
BR
Y
-G
BL
1
2
3
BL
BR
BK
(DHW)
(CH)
M
MDV
A4
3 2 1
4
A9
3 2 1
BK (-)
1
3
St2
BL
(T
ACHO)
BR (PWM)
OR (+
)
2
4
5
VM (R)
CMP (*)
2
1
GR (WSC)
BL
(YONOS) (-)
BR
MODULA
T
.
(+12 V) NOT
USED
P
N
L1
1 2
A8
3 4
5
MDV
A1
4 3 2 1
8 7 6 5
9
DK
WH
FLS SS SR
BR
WH
BR
WH
WH
R
R
1 - COM
4 - NO
A1
4 3 2 1
8 7 6 5
9
DK
WH
SS SR
BR
WH
WH
BR
BL
1 - COM
4 - NO
R
C
R
C
T.ACC
230
V
50 Hz
L
1
N
G
N
D
Y/
G
BL
BR
1
2
A7
1
2
3
4
A5
5
6
1
2
3
4
5
A8
4
A9
3 2 1
A1
4 3 2 1
8 7 6 5
9
A2
4 3 2 1
7 6 5
A4
3 2 1
A3
4 3 2 1
6 5
A6
MEMORY
CARD
VM (A)
1
2
3
St1
BL
BR
Y/
G
L1
N
L1
N
C.I. A.P.S.
BR
Y
-G
BL
GR
WH
R
(DHW)
(CH)
E. ACC./RIL.
R
A2
4 3 2 1
7 6 5
TLC TL
SRR
G
G
WH
WH
WH
BL
A6
VI
WH
R
(Mod)
(On/Of
f)
+
-
VG
EV2
EV1
OR
+
-
A3
4 3 2 1
6 5
SE
BK
TA 1/OT
TA 2
WH
WH
Y
Y
BK
BK
MDV
PK (WSC)
(YONOS)
GND
WH
SL
BK
CASING
4.5 - wIRING DIAGRAM
Practical connection board
KEY
A1.....A9
Services connectors
CMP
Modulating pump control
DK
Water deficiency safety pressure switch
E. ACC./RIL
Ignition/detection electrode
FLS
Domestic hot water request flow switch
MVD
Diverter valve motor
P
Pump
SR
Flow heating sensor
SRR
Return heating sensor
C.I
System filling
A.P.S. Additional Pump
Supply
SS
Domestic hot water probe (Pred. for R models)
TL
Limit thermostat
TLC
Flue gas collector limit thermostat
VG
Gas valve
VM
Modulating fan
SE
External probe connection terminals
TA1 / OT
Modulating TA connection terminals
TA2
On/off TA connection terminals