26
8.1 EXTERNAL WIRING
To allow basic operation of the boiler via the mode selector
switch a link must be fitted across the (‘CN5’) terminals on the
PCB. 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 Vokèra technical on 0844 391 0999.
8.1.1 EXTERNAL WIRING LIMITATIONS
Any external wiring must remain within the limits as detailed:
room thermostat = 30-metres
8.2 TYPICAL CONTROL APPLICATIONS
The appliance can be used with the following controls:
•
single-channel, voltage-free time clocks (fig. 35)
•
programmable room thermostats (fig. 36)
•
programmable RF room thermostats (fig. 35)
•
low voltage (24Vdc) room thermostat (CN5 fig. 35)
8.3 OTHER DEVICES
Contact the controls manufacturer and/or Vokèra technical
department should you require more specific information on
the suitability of a particular control. Further guidance on the
recommended practice for the installation of external controls,
can be found in CHeSS – HC5/HC6 (www.energyefficiency.gov.uk).
8.4 VOKÈRA LOWER COVER MECHANICAL
CLOCK (fig. 3)
The Vokèra lower cover mechanical clock kit (product code
20025081) is entirely suitable for the Compact 24SE and
eliminates the need for an external time control.
The kit is comprised of the following:
•
lower cover
•
mechanical clock
•
wiring harness
•
instructions
Isolate the appliance from the electrical supply, remove the
boiler casing (se 4.7.1) and locate the terminal block cover (see
4.7.2).
Connect the spade connections of the wiring harness to the
terminal block:
- identify the 2 black wiring (black color or black cable
indication) and connect to the room thermostat terminal block
(CN5 see fig. 35)
- identify the blue and brown wiring (blue/brown color or blue/
brown cable indication) and connect to the M3 terminal block
(see fig. 35).
Refit the appliance terminal block and the boiler casing.
Fit the cover kit to the boiler.
IMPORTANT
•
The boiler must always be supplied with a permanent 230V
electrical supply.
•
Always remove any links between TA & TA on the CN5 PCB
terminal (see fig. 35)
•
The room thermostat connection is low voltage (24 Vdc)
•
Do not connect any controls or auxiliary equipment to the
low-voltage terminal strip, other than that approved/supplied
by Vokèra Ltd.
Fig. 35
Fig. 36
SECTION 8 - WIRING DIAGRAMS
MECHANICAL CLOCK -
RADIO FREQUENCY RECEIVER