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INSTALLATION
Installation
Note
With a conductivity >1000 μS/cm, desalination treatment
is recommended in order to avoid corrosion.
Note
If you treat the fill water with inhibitors or additives, the
same limits as for desalination apply.
Note
Suitable appliances for water softening, as well as for
filling and flushing heating systems, can be obtained via
trade suppliers.
Minimum flow rate
The appliance is designed in such a way that no buffer cylinder
is required to provide hydraulic separation of the flow in the heat
pump circuit and the heating circuit in conjunction with area heat-
ing systems. If several heating circuits are used, we recommend
using a low loss header.
Note
The minimum flow rate must be maintained at every
operating point of the heat pump to ensure perfect heat
pump operation (see "Commissioning/ Commissioning").
To do this, the following options are available:
Install a remote control in a lead room and open this
heating circuit fully.
Install a low loss header or buffer cylinder.
The lead room is the room where the remote control is installed,
preferably the living room or bathroom. The lead room can be
regulated with an external programming unit, or indirectly by ad-
justing the heating curve. See chapter "Operation/ MAIN MENU/
SETTINGS
/ HEATING" in the operating instructions.
If an underfloor heating thermostat is installed, it should be set
with a sufficient differential (at least 20K) from the maximum
set heating circuit temperature. The electrical connection of the
underfloor heating thermostat is shown in chapter "Specification/
Connection examples".
Cooling is only possible in conjunction with a buffer cylinder or
low loss header.
!
Material losses
In the "ACTUAL VALUES" menu, the appliance offers the
option to display the water pressure.
Ensure that the pump does not run without water.
5.5 Water connection
!
Material losses
Never install the push-fit connectors in the DHW line.
Never install the push-fit connectors to the solar flow or
solar return connections. Only install the push-fit con-
nectors in the heating circuit.
Stainless steel, zinc-plated steel, copper or plastic pipework are
approved materials for the cold water line.
We approve stainless steel, copper or plastic pipework for the
DHW line.
Remove the protective caps from the cold water inlet and
DHW outlet connections.
Safety valve
The appliance is a sealed unvented DHW cylinder. Provide the
appliance with a pressure relief valve.
Install a type-tested safety valve in the cold water supply
line. The response pressure of the safety valve must be below
or equal to the permissible operating pressure of the DHW
cylinder.
The safety valve protects the appliance against unacceptable ex-
cess pressure. The diameter of the cold water supply line must be
no greater than the diameter of the safety valve.
Ensure that the expansion water escaping from the safety
valve can drip into a drain, e.g. a tank or funnel.
Ensure the drain cannot be shut off.
Size the drain so that water can drain off unimpeded when
the safety valve is fully opened.
Ensure that the discharge pipe of the safety valve is open to
atmosphere.
Fit the discharge pipe of the safety valve with a constant
downward slope and in a room free from the risk of frost.
Pressure reducing valve
Bear in mind that, depending on the static pressure, you may also
need a pressure reducing valve.
DHW circulation
DHW circulation is not recommended for reasons of poor energy
efficiency. If, however, DHW circulation is nevertheless required
because lines are routed awkwardly, it must always be designed
in accordance with applicable standards, i.e. with time and tem-
perature control. A DHW circulation set can be found in our range
of accessories.
5.6 Filling the DHW cylinder
The DHW cylinder can be filled via the cold water inlet connection.
Open one or more hot water draw-off points to fill the DHW
cylinder.
Close the hot water draw-off points once the cylinder is full.
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