Technical data
Heating system types
10
Heating system types for modulating boilers (continued)
System type 2 – Single-boiler system with shunt pump and return valve for raising the return temperature
in conjunction with
Vitorond 200, VD2
A Boiler with Vitotronic 300
B Domestic hot water tank
C Heating circuit with mixing valve
plugs
! Outdoor temperature sensor
? M2 Supply temperature sensor,
mixing valve circuit 2
? M3 Supply temperature sensor,
mixing valve circuit 3
§ Boiler temperature sensor
% DHW tank temperature sensor
aJA Temperature sensor T1
aJB Temperature sensor T2
sÖ M2 Heating circuit pump, mixing
valve circuit 2
sÖ M3 Heating circuit pump, mixing
valve circuit 3
sA Circulation pump for heating
the DHW tank
sK DHW re-circulation pump
sL Shunt pump
fÖ Power supply connection,
120 VAC
fA Burner (1st stage)
gS A1 Mixing valve motor for raising
the return temperature
gS M2 Mixing valve motor, mixing
valve circuit 2
gS M3 Mixing valve motor, mixing
valve circuit 3
lÖ Burner (2nd stage/modulating)
aVD Connection of external
equipment (see page 38)
aVH Connection of external
equipment (see page 39)
*1
On the Vitorond the boiler supply and return are at the rear of the boiler.
5285 941 v.1.5
M2 M3
29
52
2
20
52
2
20
52
5
21
28
1
B
C C
2
20
52
M3
A
90
41
40
146
143
3
17A
17B
T1
T2
*1
2
20
52
M2
A1