Installation and operating instruction
Oil condensing boiler WTC-OB 18-B
11 Technical documentation
83311002 1/2018-03 La
103-132
11.2.2 Boiler electronics WCM-OB-CPU
Signal
Signal
L
N
N'
N
L
N
L
N
N
L
L
N
L
N
L
N
L
N
L
N
L
N
L
N
L
L'
n.c.
n.c.
NTC2
NTC1
NTC2
NTC1
NTC2
NTC1
+5 V
GND
PWM
+-
+-
-
+5 V
-
P
GND
PWM
Hall
+
W
C
M-O
B-C
P
U
1
2
3
4
5
6
7
8
9
0
q
w
e
t
z
u
i
o
p
a
s
d
g
f
h
r
1
Switch S1 (WCM-CUI)
2
Condensate lift pump
3
Circulation pump voltage supply
4
Three way valve actuator (version W)
5
Fan voltage supply
6
Heat exchanger oil preheating
7
Stage 2 oil solenoid valve
8
Stage 1 oil solenoid valve
9
Pump motor
0
Ignition unit
q
Flame sensor
w
Reserve
e
Reserve
r
Reserve
t
Oil preheater temperature switch
z
PWM signal fan return signal
u
Flow sensor
i
Combustion air sensor
o
Combustion chamber pressure sensor
p
Alarm condensate lift pump / level switch
a
System pressure sensor/return flow sensor
s
Reserve (not used)
d
Flue gas sensor
f
PWM signal circulation pump
g
Remote control station (eBus FS)
h
WCM diagnostic (eBus PC)