Buderus Logamax plus Installation Instructions Manual page 31

7.1.2 Low voltage connections
WARNING
due to electric shock.
Make sure no power is supplied to the boiler
when making connections.
Connect all components to the relevant terminals:
RC Terminal - Room Controller
Connect a Room- or Cascade controller to the orange
RC terminal (fig. 31). See also paragraph 7.1.4.
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. 31).
WA Terminal - Potential-free heat demand
With this connection the room temperature-based modu-
lating 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. 31). The maximum allowed resistance of
this circuit is 100 ohms.
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 one
DHW temperature sensor in the boiler.
Connect a DHW temperature sensor suitable
for this particular boiler.
Logamax plus GB162-80 kW/100 kW - Subject to modifications resulting from technical improvements!
Electrical connections
FA FW
RC WA EV DWV
1 2 3 4 5 6
Fig. 31 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 three-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
7
Netz
PZ
PK PS
7 8 9 10
31