32
8.1
EXTERNAL WIRING
The appliance comes with a factory
fi
tted (TA) link
to allow basic operation of the boiler via the mode
selector switch. If external controls are to be
added to the system, they must be connected to
the appliance as shown in the following diagrams.
For advice on controls that are not featured in this
book, please contact Vokera technical on 0844
391 0999.
8.1.1 EXTERNAL WIRING LIMITATIONS
Any external wiring must remain within the limits
as detailed in the table below:
CONNECTION
MAX. LENGTH
External sensor
30-metres
Room thermostat
30-metres
OT+ connection
30
-metres
240V cables must be wired separately from 24V
cables to avoid interference.
8.2
TYPICAL CONTROL APPLICATIONS
The appliance can be used with the following
controls:
•
OT+ control (
fi
g. 49), please contact Vokera
technical for detailed instruction on speci
fi
c
OT+ controls.
Male connector is factory
fi
tted to be used with
OT+ control female connector.
•
single-channel, voltage-free time clocks or
programmable room thermostat (
fi
g. 48). If
using the factory
fi
tted male/female connector,
the pink wires connected to the terminal strip
M6 must be moved over to the room thermo-
stat socket position.
Vokera external sensor (
fi
g. 50)
Fig. 50
M2
External alarm
M6 E.S.
= external
sensor
OT+
=
ope connection
OPTIONAL DEVICE (24V) TERMINAL BLOCK
Fig. 49
8.3
OTHER DEVICES
Contact the controls manufacturer and/or Vokera
technical department should you require more
speci
fi
c information on the suitability of a par-
ticular control. Note if
fi
tting other controls, we
would suggest removing the factory
fi
tted male
connector wires for ease of installation. Further
guidance on the recommended practice for the
installation of external controls can be found in
CHeSS – HC5/HC6 (www.energyef
fi
ciency.gov.
uk).
IMPORTANT
• The boiler must always be supplied with a
permanent 230V electrical supply.
• Always remove the link between TA & TA on the
appliance high-voltage terminal strip whenever
additional controls are connected to the appli-
ance.
• Do not connect any controls or auxiliary equip-
ment to the low-voltage terminal strip, other
than that approved/supplied by Vokera Ltd.
N L
Fuse 3.15A F
230 V
M3
F
blue
brown
MMM
pink
pink
4
1
2
3
AMP
4
1
2
3
AMP
4
3
2
1
AMP
4
3
2
1
AMP
black
black
blue
brown
Fermale connector
Male connector
M6
OT+
M2
white
EXTERNAL
ALARM
ROOM
THERMOSTAT
(24 Vdc)
−t°
EXTERNAL
SENSOR
black
M6
OT+
SECTION 8 - WIRING DIAGRAMS
Fig. 48