Low Voltage Connections; Vac Connections - Buderus Logamax plus GB162-L.B. 80 kW Installation Instructions Manual

1
Fig. 36 Routing the cable
7.1.2

Low voltage connections

WARNING:
due to electric shock.
▶ Make sure no power is supplied to the boiler when
making connections
RC FA WA FW EV DWV
1 2 3 4 5 6
Fig. 37 External connection board connections
no. abbr. color component
1 RC orange Room controller RC and EMS bus
2 FA blue Outdoor-temperature sensor
3 WA green Potential free On/off thermostat
4 FW grey DHW temperature sensor
5 EV red External switch contact, potential free,
e. g. for floor heating safety
6 DWV green Connection for external 3-way valve
7 PK green External heating pump 120 VAC (for use
with non Buderus pump group)
8 PS grey DHW tank pump 120 VAC
9 PZ lilac DHW recirculation pump 120 VAC
10 Netz white Main power connection 120 VAC
Table 9 External connection board connections
Logamax plus GB162-L.B. 80 kW / 100 kW – 6720645916 (2014/10)
2 3
6 720 646157-33.1N
RC FA WA FW
7 8 9 10
6 720 646157-34.1N
▶ Connect all components to the relevant terminals:
RC Terminal - Room Controller
▶ Connect a Room- or Cascade controller to the orange RC terminal
( fig. 37) ( § 7.1.4, page 26).
FA Terminal - 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
( fig. 37).
WA Terminal - Potential-free heat demand
With this connection the room temperature-based modulating function
of the boiler is not used. This has a negative effect on comfort and energy
consumption. The boiler will now only modulate up to the preset space
heating water temperature.
▶ Connect the potential-free heat demand contact (On/Off
thermostat) or relay panel end switch to the green WA terminal
( fig. 37).
The maximum allowed resistance of this circuit is 100 Ω.
NOTICE
▶ The RC and WA terminals cannot be used
simultaneously.
FW Terminal - DHW temperature sensor
▶ Connect the external DHW temperature sensor to the grey FW
terminal, using the harness enclosed with the DHW temperature
sensor.
NOTICE
▶ It is not possible to connect more than 1 DHW
temperature sensor in the boiler.
▶ Connect a DHW temperature sensor suitable for this
particular boiler.
EV Terminal - External switching contact
An external switch contact can be used, i.e. to safeguard a floor heating
system so that the heating water temperature will not become too high
etc.
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 ( fig. 37).
▶ Connect the external switch contact to the red EV terminal
( fig. 37).
DWV Terminal - 3-way valve
▶ Do not use this connection.
7.1.3

120 VAC connections

NOTICE
▶ Use the 120 VAC connections for specific hydraulic
configurations and a corresponding controller.
7
Electrical connections
25