Viessmann VITOCAL 222-S Installation And Service Instructions Manual page 103

Repairs
(cont.)
Draining secondary side heat pump
1. Close the on-site boiler drain & fill
valve.
Checking the sensors
Sensor
■ Outside temperature sensor (F0)
■ Buffer temperature sensor (F4)
■ Cylinder temperature sensor (F6)
■ Flow temperature sensor, system
(F13)
■ Flow temperature sensor, cooling
circuit (direct heating circuit A1/
HC1 or separate cooling circuit
SKK) (F14)
■ Room temperature sensors
■ Flow temperature sensor, secon-
dary circuit (F8)
■ Return temperature sensor, sec-
ondary circuit (F9)
■ Flow temperature sensor, secon-
dary circuit upstream of instanta-
neous heating water heater
(LWT)
■ Liquid gas temperature sensor
(IRT)
■ Temperature sensor, refrigerant
inlet, evaporator (OCT)
■ Temperature sensor, evaporator
(OMT)
■ Temperature sensor, air intake,
evaporator (OAT)
■ Compressor head temperature
sensor (hot gas) (CTT)
2. Drain the heat pump at the secondary
circuit fill & drain valve (see chapter
"Overview of internal components:
Internal unit").
Captur- Installed loca-
ing ele- tion
ment
NTC Internal unit (see
10 kΩ page 97)
Pt500A
(PTC)
NTC
10 kΩ
NTC External unit
10 kΩ (see page 99)
NTC External unit
50 kΩ (see page 99)
Troubleshooting
Connection
Controller and
sensor PCB (see
page 49)
AVI PCB (see
service instruc-
tions
Vitotronic 200,
type WO1C)
Refrigerant circuit
control (observe
label on the exter-
nal unit)
Refrigerant circuit
control (observe
label on the exter-
nal unit)
103