Viessmann VR1 22 Installation And Service Instructions Manual page 44

Connections
Installation Examples - Vitotronic
Legend
A Heating circuit
B Spring-loaded flow check valve
C Circulation pump
D Automatic air vent, (field supplied),
pressure relief valve, and temperature pressure guage
E Expansion tank
F Domestic hot water storage tank (indirect-fired)
G 4-Way mixing valve
H Low water cut-off (if required)
44
Vitorond 100, VR1 22 to 33, 91 to 140 Installation and Service
(continued)
With one low-temperature circuit with 4-way mixing valve,
one high temperature circuit, and with domestic hot water
production
e.g. with Vitotronic 200, Model KW2 combined with
one mixing valve actuator accessory kit