Draining The Heat Pump On The Primary/Secondary Side; Checking Sensors - Viessmann KWT Vitocal 300-G Pro Installation And Service Instructions Manual

Troubleshooting
Repairs
(cont.)
Secondary circuit return temperature sensor
qR
Filter dryer
qT
Only type WW 302.B125, WW 302.B155, WW 302.B200, WW 302.B250, WW 302.B300:
qZ
Second parallel filter dryer
Condenser
qU
qI Evaporator
Primary circuit return temperature sensor (heat pump brine outlet)
qO
Secondary circuit flow temperature sensor
wP
Primary circuit flow temperature sensor (heat pump brine inlet)
wQ
Flow switch
wW
Frost stat
wE
Temperature sensor for frost stat
wR
wT Sight glass, if installed

Draining the heat pump on the primary/secondary side

Drain the heat pump at the on-site drain valve (pri-
mary/secondary side).

Checking sensors

Sensor
Outside temperature sensor (F0)
■
Flow temperature sensor, heating circuit M2/HC2 (F12)
■
Cooling circuit flow temperature sensor (direct heating circuit
■
A1/HC1 or separate cooling circuit SKK) (F14)
Room temperature sensors
■
Buffer temperature sensor (F4)
■
Cylinder temperature sensor (F6)
■
Flow/return temperature sensor, secondary circuit (F8/F9)
■
System flow temperature sensor (F13)
■
Boiler water temperature sensor, external heat generator
■
(F20)
All sensors in the heat pump refrigerant circuit
Temperature sensors, type NTC 10 kΩ
20
10
8
6
4
2
1
0.8
0.6
0.4
10 30 50 70
Temperature in °C
Fig.46
70
90 110
Test element
10 kΩ (NTC)
10 kΩ (NTC)
Temperature sensors, type Pt500A
600
580
560
540
520
500
480
460
440
420
400
-40 -30 -20 -10 0
Outside temperature in °C
Fig.47
Connection/installation
position
See controller and sensor
PCB (see page 46)
10 20 30 40