External Wiring; Replacing Pre-Fitted Mains Cable - Zanussi ULTRA+ COMBI 30 Installation And Servicing

2.20 EXTERNAL WIRING

External Controls – 230V 50Hz
Wiring a 230V 50Hz Room Thermostat,
Diagram A (with optional timer, Diagram
B)
1. Remove the link wire from the room
stat/timer plug.
2. Connect the external cable from
the room stat/timer across these
two connections, if a general live
connection is used for the room stat
or timer then connect this to the
fused spur, on the load side (see
Diagram C)
3. If the room thermostat has
compensation and requires a neutral
connection, make this connection to
the fused spur, on the load side.
DIAGRAM A:
DIAGRAM A:
Programmable Room Stat or
Programmable Room Stat or
Room Stat with Internal Timer
Room Stat with Internal Timer
Optional Room Stat or
Optional Room Stat or
Frost Programmable
Frost Programmable
Stat Room Stat
Stat Room Stat
Room
Frost
Frost Room
L N
Stat Stat/
L N
Stat Stat/
Timer
(Optional)
Timer
(Optional)

2.21 REPLACING PRE-FITTED MAINS CABLE

DIAGRAM C:
DIAGRAM C:
Use of General Live for Room Stat
Use of General Live for Room Stat
If it is necessary to use an alternative mains cable to the one pre-fitted then use
the following guide.
Room Stat
Optional
Room Stat
Optional
Frost
Frost
Replacement wiring should comply with notes in Section 2.18 and be carried out Stat
Stat
by a qualified person to avoid a hazard.
1. Isolate the mains supply to the boiler.
Mains In
Mains In
2. Remove the front panel. Refer to Section 3.2.
3. Swing the control box down into the service position, unclip and swing back the
Frost Room
Frost Room
L N
L N
Stat Stat/
Stat
Stat/
installer wiring cover to latch into the retaining clips. Refer to Section 3.8.
(Optional) Timer
Timer
(Optional)
4. Unplug the mains connector and release the cable from strain relief.
5. Unscrew the L N & E connections & remove wires from connector.
6. Remove the mains cable by pulling back through the grommet.
7. Route the replacement cable through the grommet and re-fit in reverse order.
8. Close the installer wiring cover ensuring that it is located correctly and that the
cable is retained into the strain relief as shown.
9. Swing the control box back up into the operating position and re-fit the front
panel ensuring a good seal is made.
NOTE. When making the mains electrical connections to the boiler it is important
that the wires are prepared in such a way that the earth conductor is longer than
the current carrying conductors, such that if the cord anchorage should slip, the
current carrying conductors become taut before the earthing conductor.
Installation and Servicing
SECTION 2 - INSTALLATION
Optional External Controls – Extra Low
Voltage
Wiring OpenTherm Room Control or other
OpenTherm Master Device, Diagram D.
1. Remove the timer link plug inside the
timer option cover, located on the
front of the control box
2. Unclip the timer link socket from the
aperture on the rear of the control box,
locate the plug on the same harness
branch and connect these together.
3. Using the rubber bung located
adjacent to these connections, insert
it into the open aperture.
4. Locate the OpenTherm connection on
the right hand side of the boiler installer
connections area and connect the 2 core
cable from the OpenTherm device.
DIAGRAM B:
DIAGRAM B:
Room Stat with External Timer
Room Stat with External Timer
Optional
Optional
Frost
Frost
Stat Room Stat
Room Stat Timer
Stat
Frost Room
Frost Room
L N
Stat L N Stat/
Stat Stat/
(Optional) Timer
Timer
(Optional)
Frost Protection
If parts of the pipework run outside the
DIAGRAM A:
house or if the boiler will be left off for more
than a day or so then a frost thermostat
Programmable Room Stat or
should be wired into the system.
Room Stat with Internal Timer
This is usually done at the programmer, in
Optional Room Stat or
which case the programmer selector switches
Frost Programmable
are set to OFF and all the other controls
Stat Room Stat
MUST be left in the running position.
The frost thermostat should be sited in a
cold place but where it can sense heat
from the system.
Wiring a system frost thermostat, see
Room
Frost digarams A, B and C. Wire the frost
L N
Stat Stat/
thermostat across the two connections as
Timer
(Optional)
shown.
Note. If the boiler is installed in a garage it
may be necessary to fit a pipe thermostat,
preferably on the return pipework.
DIAGRAM C:
Use of General Live for Room Stat
Room Stat
Optional
Frost
Stat
Timer
Mains In
Room
Frost
L N
Stat Stat/
Timer
(Optional)
Strain Relief
DIAGRAM B:
Room Stat with External Timer
Optional
Frost
Room Stat
Stat
Frost Room
L N
Stat
Stat/
Timer
(Optional)
DIAGRAM D:
OpenTherm Device
DO NOT CONNECT 230V TO THESE
TERMINALS OR THE BOILER ELECTRONICS
WILL BE DAMAGED
OpenTherm Device
E.G. Honeywell OT
Bridge R8810
Open Outside
Therm Sensor
6
4
Timer
33