www.stiebel-eltron.com 5
3. Appliance description
3.1 Properties
The appliance is an air | water heat pump that operates as a heat-
ing heat pump for outdoor installation. Heat is extracted from the
outdoor air at a low temperature level, and is then transferred to
the heating water at a higher temperature. The heating water can
be heated up to a flow temperature of 65°C.
The appliance is equipped with an electric emergency/booster
heater (NHZ). To safeguard heating operation and the provision
of high DHW temperatures, the electric emergency/booster heat-
er is activated as an emergency heater if the dual mode point is
undershot in mono mode operation. If the same thing happens in
mono energetic operation, the electric emergency/booster heater
is activated as a booster heater.
This appliance has further operational characteristics:
- Suitable for underfloor and radiator heating systems.
- Preferred for low temperature heating systems.
- Extracts heat from the outdoor air even at outside tempera-
tures of -20°C.
- Corrosion-protected, external casing made from hot-dipped
galvanised sheet steel plus stove-enamelled finish.
- Comprises all components and safety equipment required for
operation.
- Filled with non-combustible safety refrigerant.
Note
For centralised control of the heating system, you would
need the WPM heat pump manager.
3.2 Function
3.2.1 Heating
Heat is extracted from the outdoor air via the heat exchanger
(evaporator) on the air side. The evaporated refrigerant is com-
pressed by a compressor. This process requires electrical ener-
gy. At this point, the refrigerant is at a higher temperature level.
A further heat exchanger (condenser) transfers the heat to the
heating circuit. The refrigerant then expands again and the cycle
restarts from the beginning.
At air temperatures below approx. 7°C, the humidity in the air
condenses as hoarfrost on the evaporator fins. This hoarfrost is
automatically defrosted. Water created by this defrosting process
collects in the defrost pan and is drained off.
!
Material losses
During the defrost cycle, the fan is switched off and the
heat pump circuit is reversed. The heat required for de-
frosting is drawn from the buffer cylinder. For operation
without a buffer cylinder, observe the information in the
instructions for the WPM and parameter BUFFER OPERA-
TION in menu SETTINGS/ STANDARD SETTING. Otherwise
the heating water freezes under unfavourable conditions.
The heat pump automatically reverts to heating mode at the end
of the defrost cycle.
!
Material losses
In dual mode operation, return water from the second
heat generator may flow through the heat pump. Please
note that the return temperature must be no higher than
60°C.
3.2.2 Cooling
!
Material losses
The heat pump is not suitable for continuous, year-round
cooling.
Observe the application limits (see chapter "Specifi-
cation/ Data table").
!
Material losses
In cooling mode, condensate can form when the dew
point temperature is undershot.
Take suitable measures to prevent the formation of
condensate.
Rooms are cooled by reversing the heat pump circuit. Heat is
extracted from the heating water and the evaporator transfers
this heat to the outdoor air.
Area cooling and fan cooling require the installation of a remote
control unit (FEK/FET) in a reference room to capture the rel-
ative humidity and the room temperature as part of dew point
monitoring.
With fan cooling, it is also necessary to install a buffer cylinder.
Heat pump application limit
The heat pump is switched off if the outside temperature falls
below the selected lower application limit for cooling (COOLING
LIMIT parameter).
4. Settings
The system is operated exclusively via the WPM heat pump man-
ager.
Please observe the instructions for the heat pump manager.
To Next Page
Loading...
Need help?
General
