Worcester GB162-50 Installation And Servicing Instructions page 28

Installation
Connecting the outdoor temperature sensor
If outdoor temperature-dependant control operation is used, an outdoor
temperature sensor must be connected.
▶ Connect the outdoor temperature sensor to the blue FA terminal,
using a 2-core cable of 0.75 mm².
This connection is non polarity sensitive. This means that
it does not matter which order the wires are connected.
FA
Fig. 47 Terminal strip - Outdoor-temperature sensor (connection
colour blue)
Connecting the potential-free heat demand
▶ Connect the potential-free heat demand contact to the green WA
terminal ( fig. 48). The maximum allowed resistance of this circuit
is 100 Ω. Use a 2-core cable of 0.75 mm².
WA
Fig. 48 Terminal strip - potential-free heat demand (connection colour
green)
NOTICE:
▶ It is not possible to connect a thermostat
simultaneously to the RC connection and to the
terminal for the potential-free heat demand (WA)
( fig. 49).
▶ It is possible to operate the boiler with an On/Off
contact for potential-free heat demand, but the room
temperature-based modulating function of the boiler
cannot then be used anymore. This has a negative
effect on comfort and energy consumption. If an On/
Off contact for potential-free heat demand is
installed, the boiler will only modulate up to the
preset CH flow temperature.
▶ This connection is reverse-proof. This means that it
does not matter which order the wires are
connected.
WA
Fig. 49 Terminal strip - WA potential-free heat demand
28
Connecting the DHW temperature sensor
▶ Connect the DHW temperature sensor to the grey FW terminal, using
the harness enclosed with the DHW temperature sensor [1].
6 720 648 726-047.1TD
Fig. 50 Terminal strip - potential-free heat demand (connection colour
Connecting an external switch contact
A potential-free external switch contact can be connected. This external
switch contact can be used to safeguard a underfloor heating system so
that the heating water temperature will not become too high etc.
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When the external switch contact is opened, the boiler will be switched
off for heating operation and for domestic hot water operation.
The pump continues to run for the run-over time set on the boiler.
▶ Remove the cable from the EV terminal.
▶ Connect the external switch contact to the red EV terminal.
Fig. 51 Terminal strip - external switch contact, potential-free, e. g. for
Connecting external 230 V controls with use of the 230 Volt
converter (only for GB162-50/65)
The gas wall hung boiler condensing can be fitted with the following
external controls:
• a room-temperature control device at 230 V connected to the room
control converter (only for GB162-50/65). For connection, see the
electrical wiring diagram supplied with the 230 Volt converter),
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• ON/OFF temperature controller, Volt free.
NOTICE:
▶ This connection is reverse-proof. This means that it
does not matter in which order the wires are
connected.
▶ It is not possible to connect more than one DHW
temperature sensor in the boiler. It is only possible to
connect a DHW temperature sensor which is suitable
for this boiler.
green)
This connection is reverse-proof. This means that it does
not matter in which order the wires are connected.
floor heating (connection colour red)
1
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EV
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