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Elecrical connection
49
Greenstar FS/Combi FS – 6 720 810 590 (2020/04)
Fig. 49 Attach plug (external DHW tank loading pump or 3-way valve)
[1]
L (120VAC, 60Hz)
[2]
PE (GND, ground)
[3]
N (Neutral)
[4]
Red plug (in the junction box upon delivery)
▶ Connect red plugs and insert grommet until stop.
Fig. 50 Cable connected (external DHW tank loading pump or 3-way
valve)
▶ Mount the 3-way valve for space heating operation when
deenergized, and DHW tank loading when energized.
▶ Use service function 1.F to set pump mode. (
page 56).
7.1.6
Connecting mains power supply
▶ Route the power cable (AC 120 V, 60 Hz) from the emergency shutoff
switch to the boiler.
▶ Insert cable into the junction box as shown in Fig. 52.
▶ Connect cable to the
white plug
according to Fig. 51.
Fig. 51 Attach plug (mains power supply)
[1]
L (120Vac, 60Hz)
[2]
PE (GND, Ground)
[3]
N (Neutral)
[4]
White plug (in junction box with delivery)
▶ Connect white plugs and insert grommet until stop.
Fig. 52 Cable connected (mains power supply)
▶ Mount junction box on the rail.
7.1.7
Low voltage (LV) junction box
The low voltage installer junction box provides connections to sensors,
thermostat and programmers.
Bosch room controls
Connect only Bosch room controls to the internal BUS of this boiler.
For installation and electrical connection of Bosch controls, see
installation instructions for the Bosch control.
Connecting external manual reset high limit or low water cut off
(LWCO)
This connection allows the installation of external safety switches.
Remove the link if using these connection points
• External manual reset high limit
• Low water cut-off (LWCO)
• Radiant overheat protection
Fig. 53 Low voltage (LV) connections
1
2
3
4
6 720 641 933-37.2O
6720810590-60.2W
o
L PE N
white
Mains
120V/60H
z
L PE N
red
Storage
tank pump
L PE N
black
CH pump
for mix
ed heating
8 737 701 503
I III III III
1
2
3
4
6 720 641 933-36.2O
6720810590-61.2W
o
L PE N
white
Mains
120V/60H
z
L PE N
red
Storage
tank pump
L PE N
black
CH pump
for mix
ed heating
8 737 701 503
I III III III
6720810590-68.1Wo