Section 8: ElectricalPage 26
! WARNING !
Ensure that the electrical supply has been isolated before
making any connections to the boiler.
8.1 GENERAL
Grant Vortex Pro External models require a ~230V 1ph 50Hz
supply. It must be protected by a 5 Amp fuse.
Refer to Figures 8-1 and 8-2 for typical control system wiring
diagrams for all models.
Refer to Figure 8-3 for control panel wiring diagrams for all Vortex
Pro External models.
! WARNING !
The Vortex boiler contains electrical switching equipment
and must be earthed.
The supply must be fused at 5 Amp and there must only be one
common isolator for the boiler and control system, providing
complete electrical isolation.
A fused double pole switch or a fused three pin plug and shuttered
outlet socket should be used for the connection.
The power supply cable should be at least 0.75 mm² PVC as
specied in BS 6500, Table 16.
All the wiring and supplementary earth bonding external to
the boiler must be in accordance with the current IET Wiring
Regulations.
Any room thermostat or frost thermostat used must be suitable for
use on mains voltage.
In the event of an electrical fault after installation of the boiler, the
following electrical system checks must be carried out:
• Short circuit
• Polarity
• Earth continuity
• Resistance to earth
! NOTE !
If the supply cord is damaged, it must be replaced by
the manufacturer, its service agent or similarly qualied
persons in order to avoid a hazard.
8.2 CONNECTING THE POWER SUPPLY
It is recommend that the boiler should be connected to a switched
mains power supply from a programmer or control system.
A three core cable is required to connect the boiler terminal block
to the live supply.
Refer to Figures 8-1 and 8-2 for typical control system wiring
diagrams.
! NOTE !
Ensure that the route and length of the supply cable
is such that the boiler front cover plate can be easily
removed without disconnecting the supply cable from the
terminal block.
The procedure is as follows:
1. Remove the casing door on the front of the external module,
then remove the four screws retaining the top casing panel
and remove the top casing panel.
2. Remove the three screws securing the left hand cover to the
control panel and remove this cover to gain access to the
boiler terminal block.
3. Loosen/remove the screws securing the cable clamp and
open the clamp.
4. Route the supply and pump cables into the enclosure as
outlined in Section 4.8.
5. Pass the mains power supply cable through the cable
grommet in the back of the control panel, through the cable
clamp and connect to the boiler control panel terminals as
follows:
• Brown to mains live (terminal 2)
• Blue to mains neutral (terminal 3)
• Green/Yellow to mains earth (terminal 4)
6. If the circulating pump is to be tted inside the boiler
enclosure, pass the 3-core cable from the pump through the
cable grommet and through the clamp and connect to the
boiler control panels as follows:
• Green/Yellow to pump earth (terminal 10)
• Blue to pump neutral (terminal 9)
• Brown to pump live (terminal 8)
! NOTE !
Connecting the pump in this manner allows the pump to be
isolated using the isolated switch inside the boiler control
panel, for servicing and maintenance work.
7. Make the remaining required connections to the control
panel, as detailed in Figures 8-1 and 8-2.
8. Tighten the cable clamp and ret the front of the control panel
and terminal block cover, taking care not to trap any wires.
! WARNING !
After completing electrical connections and before
reconnecting the electrical supply to the boiler, replace
the terminal block cover and secure it using the screws
provided.
9. Replace the top casing panel and four retaining screws
following the procedure outlined in Section 4.7 and replace
the casing door.
10. Re-connect the electrical supply and check operation of
heating system controls (programmer, room thermostats,
etc.).
11. Refer to Instructions provided with the programmer for
operation and setting.
12. Leave the Programmer and Thermostat Instructions with the
user after installation for their future reference.
8 ELECTRICAL