Wiring Diagram - Viessmann VITOTRONIC 300 GW2 Installation And Service Instructions Manual

Wiring diagram

(continued)
120 V~ motherboard (continued)
sÖ Heating circuit pump
or
control output
sA Circulation pump for heating the
DHW tank (accessory)
sK DHW circulation pump (installed
on site)
sL Shunt pump (installed on site)
fÖ Mains connection, 50 Hz
fA Oil/gas burner,
connection to DIN 4791
gÖ Central fault indicator (installed on
site)
gS Mixing valve motor for return
temperature control
or
3-way mixing valve for DHW tank
loading system
lÖ Burner (2nd stage/modulating)
aBÖ External equipment
a External safety equipment
(remove jumper when
connecting)
b External disable (remove
jumper when connecting)
c External burner switch-on
(1st stage)
aBA Safety circuit, potential free
aBH Mains connection for accessories
Additional information
F1, F2 Fuse
F6 Fixed high limit "E" 110°C
(99°C)
F7 Adjustable high limit "R" 95°C
K1-K10 Relay
S1 Heating system on/off switch
"8"
S2 TEST button
139