30
BS6798 provides comprehensive instruction and advice on all
permissible condensate disposal methods; notwithstanding this,
it is essential that the following is strictly adhered to:
- use only plastic drainage pipe (minimum OD of 21.5mm)
- horizontal runs must incorporate a minimum 45mm fall per
metre, away from the appliance
- external pipework and/or pipework in unheated areas, must
have a minimum OD of 32mm and be insulated with Class-O
pipe insulation
- the route, type, and termination of the condensate disposal
method, must not permit any spillage of condensate fluid,
into the dwelling in the event of a blockage or freezing of the
condesate pipework
- if there is a risk of freezing, Vokera strongly reccomends that
a tundish is incorporated within the discharge pipework (see
5.6.3 above).
Should it not be possible to route and terminate the condensate
pipework internally using ‘gravity discharge’; Vokera
recommends that the Vokera condensate pump (code 404)
be considered as an alternative solution.
Ensure that the end-user is aware of the effect/consequences
of the condensate pipework becoming blocked or frozen.
5.7 ELECTRICAL CONNECTIONS
The boiler is supplied with a fly-lead. This lead can be used for
connection to the electrical supply. Connect the fly-lead to a
fused plug or fused isolator in the following way:
• brown wire to LIVE supply
• blue wire to NEUTRAL supply
• green/yellow to EARTH connection.
Insert the supplied 3-AMP fuse into the fused isolator or fused
plug. Should the fly-lead be unsuitable, refer to section 5.7.3
for details on how to connect the electrical supply directly to
the boiler.
The electrical supply must be as specified in
section 4/4A.
A qualified electrician should connect the appliance to the
electrical supply. If controls - external to the appliance - are
required, a competent person must undertake the design of
any external electrical circuits, please refer to section 8 for
detailed instructions. ANY EXTERNAL CONTROL OR WIRING
MUST BE SERVED FROM THE SAME ISOLATOR AS THAT
OF THE APPLIANCE. The supply cable from the isolator to the
appliance must be 3-core flexible sized 0.75mm to BS 6500 or
equivalent. Wiring to the appliance must be rated for operation
in contact with surfaces up to 90 ºC.
ModBus 485 Connection (CE4)
Carry out the connections as follows:
- use connector CE4 supplied as standard:
- 4-poles ModBus connector for BUS 485 (- A B +)
- A B +
CE4
SE - OT+ connections
- Remove front cover as detailed in 5.7.1.
- Remove PCB cover (see diagram).
- Locate 4-pole terminal block (M4) connected to PCB at X11
(see diagram).
- Connect external sensor to terminals marked ‘SE’ (see dia-
gram).
- Connect Opentherm control to terminals marked ‘OT’ (see
diagram).
- Replace PCB cover and appliance front cover as detailed in
5.7.1.
black (TA)
black (TA)
pink (OT+)
pink (OT+)
orange (SE)
orange (SE)
6
1
X11
CN1
CN2
NO
NC
C
black
black
BE11
OT+
SE
M4
SWITCHED LIVE CONNECTION
Should it be necessary/required to control the appliance using
a 230V supply from an external control or wiring centre; the
switched supply (L&N) must be connected to the relay board
BE11 at terminals CN1.
See above diagram and also Section 7 (7.11 & 7.12).
Opentherm Control
When an OT control is connected to the appliance, the UI
screen will display ‘Opentherm Connected’. The control
functions of the appliance UI will be transferred to the OT
control, which can then be used to set/adjust the main heating
zone settings and the hot water settings.
UI Functions When OT Control is Connected
STATE function is disabled on the UI and must be set/adjusted
via the OT control. The outlet HW temperature cannot be
adjusted via the appliance UI, and is set/adjusted via the OT
control.
INFO Menu
When an OT control is connected, the info menu will display
the HW set-point instead of the HW flow-rate.
NOTE
All/any functions of the ‘main’ zone are disabled on the
appliance UI and can only be accessed/adjusted via the OT
control.
18/05/2013
12:17
MENU
INFO
SET
42
°C
1.5 bar
FRI
PLANT
HOT WATER TEMPERATURE
STATE
Open Therm connected
5.7.1 FRONT COVER REMOVAL
Refer to fig. 23.
- Locate and remove screws ‘
A
’ that secure the spring clips to
the underside of the appliance.
- Gently unclip the spring clips ‘
C
’ and pull the front cover
outwards and then upwards in order to disengage it from the
tabs ‘
B
’ at the top of the appliance.
- Place the front cover in a safe area to avoid any risk of da-
mage.
- Replace in the reverse order.
