Technical data

6 720 611 443 GB (03.11)
22
Electrical connections
B Secure cable in cable grommet by means of cable
grip.
Fig. 30
4.2 Wiring to your system
The boiler is fitted with an internal pump and there are
two recommended ways of connecting a system, exter-
nal 230v or internal 24v depending on the choice of
diverter valve(s).
4.2.1 External 230v
Non-supplied parts required: external 230v conven-
tional terminal block or wiring centre, pre-wired to the
230v diverter valve(s) and all other 230v system com-
ponents.
Note : Honeywell and Siemens Y plan valves require a
capacitor in the external wiring block or wiring centre
to avoid any feedback problems, if there is no other
alternative, please contact Worcester Bosch helpline
08705 266241 for further details.
•See section 4.1 to gain access to the boiler mains
wiring centre
•Remove the connecting link from Ls and Lr terminals
and connect the system to the boiler as shown in
Fig. 31
•Any other components (including frost thermostats)
cannot be connected to the boiler and should
instead be connected to the external terminal block
or wiring centre in accordance with the manufactur-
ers proprietary instructions. No liability is accepted
arising from or by any wiring external to the boiler.
Fig. 31 External 230v connections
N
S
LN
LN
N
S
L
S
L
R
Timer Tank Stat Room Stat System Water Valve/s
External pump
(DISCONNECT
AND REMOVE)
Boiler/pump
demand from
junction box.
OUTSIDE OF BOILER
INSIDE OF BOILER
L out
Terminal Strip
ELN
Mains electrical supply to junction box
(NO OTHER SUPPLY TO
JUNCTION BOX ALLOWED)
Permanent
Mains supply
(NOT ALLOWED)
Remote Pre-wired
Junction Box
6 720 610 603 -05.TD
MAINS ONLY