Draining Secondary Side Heat Pump; Checking The Temperature Sensors - Viessmann VITOCAL 200-A Series Installation And Service Instructions For Contractors

Outdoor unit: Overview of internal components
Electronic expansion valve
D
4-way diverter valve
E
Secondary circuit flow temperature sensor
F
upstream of instantaneous heating water heater
(T1)
Low pressure sensor
G
Secondary circuit air vent valve
H
Evaporator suction gas temperature sensor (T7)
K
Reversible suction gas temperature sensor (T3)
L
M Condenser
Schrader valve, low pressure side
N

Draining secondary side heat pump

1. Close the on-site boiler drain & fill valve.

Checking the temperature sensors

Connection to the indoor unit
Temperature sensors are connected to the controller
and sensor PCB: See page 44.
Temperature sensor
Outside temperature sensor (F0)
■
Buffer temperature sensor (F4)
■
Cylinder temperature sensors top (F6) and bottom (F7)
■
System flow temperature sensor (F13)
■
Cooling circuit flow temperature sensor (direct heating circuit A1/HC1 or separate cool-
■
ing circuit SKK) (F14)
Boiler water temperature sensor, external heat generator (F20)
■
For heat pump cascades: Buffer outlet temperature sensor (F23)
■
Room temperature sensors
■
For heat pump cascades: Swimming pool flow temperature sensor (F21)
■
Flow temperature sensor for secondary circuit (F8)
■
Secondary circuit return temperature sensor (F9)
■
Connection to the outdoor unit
Temperature sensors are connected to the refrigerant
circuit controller in the outdoor unit (see label in the
outdoor unit): See page 83.
Temperature sensor
Refrigerant circuit controller temperature sensor (T2)
■
Compressor suction gas temperature sensor (T4)
■
Air intake temperature sensor (T5)
■
Hot gas temperature sensor (T6)
■
Evaporator suction gas temperature sensor (T7)
■
Secondary circuit flow temperature sensor (T1)
■
Reversible suction gas temperature sensor (T3)
■
(cont.)
Hot gas temperature sensor (T6)
O
Compressor suction gas temperature sensor (T4)
P
Schrader valve, high pressure side
R
Compressor
S
T Refrigerant receiver
Safety high pressure switch
U
High pressure sensor
V
Schrader valve, high pressure side
W
Refrigerant circuit controller temperature sensor
X
(T2)
2. Drain the heat pump at the drain & fill valve in the
secondary circuit: See chapter "Indoor unit: Over-
view of internal components".
Maintenance
Test element
NTC 10 k
Ω
NTC 20 k
Ω
Pt500A
(PTC)
Test element
NTC 10 k
Ω
85