27
8.1
EXTERNAL WIRING
The appliance comes with a factory fitted 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 0870
333 0520.
8.2
TYPICAL CONTROL APPLICATIONS
The appliance can be used with the following
controls:
●
single-channel, voltage-free time clocks (fig. 39)
●
programmable room thermostats (fig. 39)
●
twin-channel programmers (figs 40 & 41). The
appliance can be used in conjunction with typi-
cal ‘S’-Plan/’Y’-Plan systems (see 8.4.1 & 8.4.2),
please contact Vokera technical should you
require further detailed instruction.
8.3
OTHER DEVICES
P2
: external pump, a supplementary pump that
can be managed directly from the boiler in order
to satisfy larger systems with high flow rate or
high pressure drop (i.e. underfloor heating).
Contact the controls manufacturer and/or Vokera
technical department should you require more
specific information on the suitability of a particu-
lar control. Further guidance on the recommended
practice for the installation of external controls,
can be found in CHeSS – HC5/HC6
(www.energyefficiency. gov.uk).
SECTION 8
WIRING DIAGRAMS
Fig. 39