Section 8: Electrical
Page 30
8.1 General Requirements
The Grant External Vecta wood pellet boiler requires a ~230V 1ph 50
Hz electrical supply. The unit must be connected to a mains power
supply that is protected by a 5A fuse.
as a stationary appliance not fitted with a means for
disconnection from the supply mains having a contact
separation in all poles that provide full disconnection under
overvoltage category iii, means for disconnection must be
incorporated in the fixed wiring in accordance with the wiring
rules.
!
WaRninG
A fused double pole switch, with contact separation of at least 3mm
in both poles, should be used for connection to the mains electrical
supply, serving the boiler and heating system controls only.
For the UK, the electrical installation must be carried out by a
competent installer in accordance with the requirements of the
Electricity at Work Regulations 1989 and BS7671:2008 – IET Wiring
Regulations 17th Edition (including all amendments).
All the wiring and supplementary earth bonding external to the boiler
must be in accordance with the above mentioned wiring regulations.
Any heating system controls, e.g. room thermostat, frost thermostat,
etc. connected to this boiler must be suitable for use on mains
voltage.
The boiler requires a permanent mains supply and switched live (for
the heating and hot water control) to operate the boiler. For details of
heating and hot water system controls refer to Sections 8.5 and 8.6.
Do NOT interrupt the permanent supply to the hopper/boiler with any
external controls.
8.2 Boiler Electrical Connections
All the electrical connections (permanent mains supply and switched
live from the heating control system) to the boiler are made via the
terminal block in the lower left corner of boiler. Refer to Figures 8-7
and 8-10.
To access the terminal block, the terminal block cover must be
removed using the following procedure:
1. Open the front door of the boiler. First unlock and remove the
padlock (if fitted), rotate the knob of the catch clockwise to
unlatch and fully open the door.
2. Switch the electrical isolator to OFF. Refer to Figure 11-4.
3. Fit the multi-purpose tool (provided with the boiler) into the slot in
the door catch. Refer to Figure 11-5.
4. Lift the tool handle to release the door catch and fully open the
combustion chamber door of the boiler. Refer to Figure 11-6.
5. Undo the seven screws and remove the grey left hand cover
panel from the boiler
6. Remove the side access panel from the left side of the boiler.
Unlock/remove padlock (if fitted). Rotate the knob of the catch
clockwise to unlatch and remove the access panel
8 Electrical
Figure 8-1:
Boiler terminal block location (cover removed)
7. Slacken and remove the four screws securing the PCB housing.
Refer to Figure 8-2.
Figure 8-2:
PCB housing screws
8. Carefully swing the PCB housing out from the side of the boiler
casing. Refer to Figure 8-3.
Figure 8-3:
PCB housing pivoted
9. It will be necessary at this point to remove the photocell from
the mount on the left side of the boiler heat exchanger. Refer to
Figure 8-4.
Figure 8-4:
Removing the photocell
