Instruction manual

ELECTRICAL
CAUTION: ISOLATE THE MAINS
ELECTRICITY SUPPLY BEFORE STARTING
ANY WORK AND OBSERVE ALL
RELEVANT SAFETY PRECAUTIONS
Note: Mains supply to the boiler must be
through a fused double pole isolator situated
adjacent to the appliance. The isolator must
have a contact separation of 3mm minimum
in all poles. External fuse rating 3A.
When stripping wires always ensure copper
strands do not fall into the control box.
There should be no external wiring centre.
A fascia mounted twin channel programmer
must be used.
Timers available:
DT20 Twin Channel Programmer
(7 716 192 038),
DT10RF Digistat (7 716 192 052),
DT20RF Digistat (7 716 192 054).
Access to electrical connections:
Remove boiler casing to access control panel.
1 Unscrew screw (A) and lower the control
box into the horizontal position.
2 Unscrew the three screws (B) in the control
panel and pull off the connections cover.
3 Central heating channel
230V room stat if required with timer
7 716 192 038 (ST10):
 Remove link
 Connect room stat LIVE supply to terminal (L
S)
 Connect room stat LIVE return to terminal (LR)
 Connect room stat NEUTRAL to terminal (NS)
Note:
If the timer 7 716 192 052 or
7 716 192 054 is used, the roomstat
is incorporated in the transmitter.
Therefore keep the link fitted.
4 Hot water channel
Volt-free cylinder stat (ST8):
 Cylinder Stat wires to terminals 7 and 9.
NOTE: The cylinder stat must be volt-free,
i.e not connected to any voltage source.
5 Optional external frost stat connection (ST6):
 Connect frost stat wires to terminal (Fs) and (FR)
6 Diverter valve motor
(ST17):
 Connect electrical harness from diverter valve
motor to ST17 (see following page).
2
B
ELECTRICAL
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR 12i/24i System
8 716 115 167b (03/2009)
29
INSTALLATION
A
1
3
4
F1
F3
F2
ROOMSTAT
230V
MAINS
SUPPLY
ST6
ST10
switched live
live
neutral
blue
green/yellow
brown
TANKSTAT
FROSTSTAT
5
calling
6
INTERNAL DIVERTER VALVE WITH A VENTED CYLINDER
THE OPTIONAL INTEGRAL
DIVERTER VALVE IS
INCOMPATIBLE WITH
A MAINS PRESSURE
UNVENTED CYLINDER.
IF INSTALLING AN
UNVENTED CYLINDER
USE AN EXTERNAL
DIVERTER VALVE.
ST8