Viessmann Vitocal 222-S Installation And Service Instructions For Contractors page 85

Overview of internal components: Indoor unit
BC D
A
W
V
U
T
S
R
Fig. 72
Condenser
A
Secondary circuit air vent valve
B
Secondary circuit flow temperature sensor
C
upstream of instantaneous heating water heater
(F3)
Reversible suction gas temperature sensor (F24)
D
Type AWBT(-M)-E/AWBT(-M)-E-AC only:
E
Instantaneous heating water heater
F Quick-action air vent valve G
E F
G
H
K
L
M
N
O
P
⅜
Secondary circuit flow temperature sensor (F8)
G
3-way diverter valve "central heating/DHW heat-
H
ing"
Safety valve
K
Pressure gauge
L
M Flow switch
Secondary pump
N
Secondary circuit air vent valve, DHW cylinder
O
Secondary circuit drain and fill valve
P
Drain and fill valve, DHW side
R
Type AWBT(-M)-E/AWBT(-M)-E-AC only:
S
High limit safety cut-out (STB), instantaneous
heating water heater
Secondary circuit return temperature sensor (F9)
T
Liquid gas temperature sensor (F25)
U
Indoor unit service valve: Schrader valve; can be
V
used in place of the outdoor unit service valve for
checking the pressure and evacuating the refriger-
ant circuit.
Indoor unit service valve: Schrader valve; can be
W
used in place of the outdoor unit service valve for
checking the pressure and evacuating the refriger-
ant circuit.
Maintenance
85