95
Draining secondary side heat pump
1.
Close the on-site boiler drain & fill
valve.
2.
Drain the heat pump at the secondary
circuit fill & drain valve (see chapter
"Overview of internal components:
Internal unit").
Checking the sensors
Sensor
Captur-
ing ele-
ment
Installed loca-
tion
Connection
■ 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
NTC
10 kΩ
Internal unit (see
page 89)
Controller and
sensor PCB (see
page 40)
■ Flow temperature sensor, secon-
dary circuit (F8)
■ Return temperature sensor, sec-
ondary circuit (F9)
Pt500A
(PTC)
■ Flow temperature sensor, secon-
dary circuit upstream of instanta-
neous heating water heater
(LWT)
■ Liquid gas temperature sensor
(IRT)
NTC
10 kΩ
AVI PCB (see
service instruc-
tions
Vitotronic 200,
type WO1C)
■ Temperature sensor, refrigerant
inlet, evaporator (OCT)
■ Temperature sensor, evaporator
(OMT)
■ Temperature sensor, air intake,
evaporator (OAT)
NTC
10 kΩ
External unit
(see page 91)
Refrigerant circuit
control (observe
label on the exter-
nal unit)
■ Compressor head temperature
sensor (hot gas) (CTT)
NTC
50 kΩ
External unit
(see page 91)
Refrigerant circuit
control (observe
label on the exter-
nal unit)
Troubleshooting
Repairs
(cont.)
5782 201 GB
Service
