Viessmann BW 301.A090, Installation And Service Instructions Manual

Page: 104 / 160

104
wQ Only type WW 302.A125,
WW 302.A155, WW 302.A200,
WW 302.A250, WW 302.A300:
Second parallel filter dryer
wW Condenser
wE
Evaporator
wR Primary circuit return temperature
sensor (heat pump brine outlet)
wT Secondary circuit flow temperature
sensor
wZ Primary circuit flow temperature
sensor (heat pump brine inlet)
wU Flow switch
wI
Frost stat
wO Temperature sensor for frost stat
eP
Sight glass, if installed
Draining the heat pump on the primary/secondary side
Drain the heat pump at the on-site drain
valve (primary/secondary side).
Checking sensors
Sensor Capturing el-
ement Connection/instal-
lation position
■ Outside temperature sensor (F0)
■ Flow temperature sensor, heating circuit M2/
HC2 (F12)
■ Cooling circuit flow temperature sensor (di-
rect heating circuit A1/HC1 or separate cool-
ing circuit SKK) (F14)
■ Room temperature sensors
Ni500 see controller and
sensor PCB (see
page 68)
■ 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)
Pt500
All sensors in the heat pump refrigerant cir-
cuit see page 99
Troubleshooting
Repairs
(cont.)
5848 164 GB