Heat Pump (Outdoor Unit); Range For Heat Pump Without Booster Heater; Generic Overview Of The Refrigerant Circuit - Bosch CS5800iAW 180 MCP Operating Instructions Manual

2.4

Heat pump (outdoor unit)

The heat pump is inverter operated, which means that it will
automatically change the compressor speed to deliver the exact amount
of energy required at the moment. The fan is also RPM controlled and will
change its speed as needed. This provides the lowest possible energy
consumption.
The speed changes have an effect on the sound emissions, as higher
speed results in higher sound emission.
Defrosting
Ice might form on the evaporator during lower outside temperatures. In
case there is enough ice to inhibit the air flow through the evaporator, an
automatic defrosting will start. As soon as the ice is gone, the heat pump
returns to its normal operation.
If the outside temperature is above +5 °C the defrosting will be
performed alongside continued heat production, however if the
temperature is lower, the defrosting is done by ways of a 4-way valve
turning the heat medium direction in the circuit so that the hot gas from
the compressor melts away the ice. The duration of the defrost cycle
depends on the actual outdoor temperature and the amount of frost on
the evaporator.
2.4.1

Range for heat pump without booster heater

In heating mode the heat pump switches off at approx. – 23 °C or +45 °C
outdoor temperature. The indoor unit or an external heat source then
takes over the heating and domestic hot water production. The heat
pump restarts if the outdoor temperature exceeds roughly – 17 °C or
falls below +42 °C.
2.4.2

Generic overview of the refrigerant circuit

75 %
+2 °C –2 °C
1
Fig. 5 Functional principle of the refrigerant circuit in the heat pump
[1] Evaporator
[2] Compressor
[3] Condenser
[4] Expansion valve
Pre plumbed cylinder – 6 721 852 929 (2023/04)
0 °C
–4,5 °C
T0[°C]
1
75
70
65
60
55
45
35
25
15
10
-30 -20 -10
Fig. 4 Heat pump in heating mode without booster heater
[1] Flow temperature (T0)
[2] Outdoor temperature (T1)
25 %
2
88 °C
4
Product Information
0 10 20 30 40
100 %
+27 °C
3
50 °C
50
T1[°C]
2
0010044796-004
+35 °C
5