Vaillant ecoTEC plus VU GB 656/4-5 A Installation And Maintenance Instructions Manual page 38

Appendix
Fan
230 V~
X13
N
L
X11
X18
Cylinder
5
charging pump
4
3
N
L
9
pink
8
X6
7
X1
+
-
2
1
1
X41
6
X22
38
N
Auxiliary relay (can be adjusted under D.26)
L
N
L
Option: Ext. controller/room thermostat 3-4
(Contact)
Mains input
Option: Ext. controller/room thermostat 7-8-9
(continuous, analogue)
Option: Bus connection (controller/digital room therm.)
Option: Contact thermostat
Earth
0
Earth
0
DCF connection
DCF
RF
Low loss header sensor
External sensor
AF
FB Circulation pump remote control
Internal pump
Plug for controller accessory
VRC 4xx or ZP control system
PWM signal: Internal pump
Installation and maintenance instructions ecoTEC plus 0020214491_01
Fan