128
M
Drain valve on the secondary side
N
Circulation pump for cylinder heat-
ing (accessory for
type BW/WW 351.A07, installation
outside the heat pump) with check
valve
O
Secondary pump (accessory for
type BW/WW 351.A07, installation
outside the heat pump) with check
valve
P
Air vent valve, secondary side
Q
Low pressure sensor EEV
R
Suction gas temperature sensor
S
Safety high pressure switch
T
High pressure sensor EEV
U
Filter dryer
V
Primary circuit return temperature
sensor (heat pump brine outlet)
W
Drain valve, primary side
X
Hot gas temperature sensor
Draining the heat pump on the primary/secondary side
1.
Shut off the connection to the heating
network.
2.
Drain heat pump at drain valve on pri-
mary/secondary side (see
page 126).
Checking sensors
Sensor
Captur-
ing ele-
ment
Installed lo-
cation
Connection to
■ Outside temperature sensor (F0)
■ Flow temperature sensor, heating
circuit M2 (F12)
■ Cooling circuit flow temperature
sensor (direct heating circuit A1/
HC1 or separate cooling circuit
SKK) (F14)
■ Room temperature sensors
Ni500
Controller and
sensor PCB
(see page 91)
■ Buffer temperature sensor (F4)
■ Cylinder temperature sensor (F6)
■ Flow/return temperature sensor,
secondary circuit (F8/F9)
■ System flow temperature sensor
(F13)
■ All sensors inside the heat pump
■ Boiler water temperature sensor,
external heat source (F20)
Pt500
Troubleshooting
Maintenance
(cont.)
5609 667 GB
