Viessmann VITOCAL 222-S Installation And Service Instructions Manual page 98

Troubleshooting
Repairs
(cont.)
?
Secondary circuit flow tempera-
ture sensor (alternative posi-
tions)
%
Cylinder temperature sensor
aJ Secondary circuit, return tem-
perature sensor
sG
Secondary pump
lJ 3-way diverter valve for "Central
heating/DHW heating"
a:DB PWM signal, secondary pump
A Cylinder air vent valve for inter-
nal coil
B Cylinder drain & fill valve (see
following chapter)
C
Instantaneous heating water
heater with high limit safety cut-
out
D
Secondary circuit drain & fill
valve
98
E
Internal unit service valve
(Schrader valve; can be used in
place of the external unit service
valve for checking pressure and
evacuating the refrigerant cir-
cuit; see page 72)
F
Liquid gas temperature sensor
(IRT)
G Secondary circuit temperature
sensor upstream of the instan-
taneous heating water heater
(LWT)
H Secondary circuit air vent valve
K Pressure sensor (ICT) for deter-
mining condensation tempera-
ture in condenser