INSTaLLaTION
Commissioning
42
| WPL 15 IKS | WPL 25 IK
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12.2 Minimum flow rate
For heating operation without a buffer cylinder, always ensure the
minimum flow rate and the availability of energy for defrosting.
12.3 Setting the flow rate on the heating side
!
Material losses
For operation without a buffer cylinder, it is essential that
the electric emergency/booster heater (DHC) is connec-
ted.
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 panel
heating systems.
We recommend the use of a buffer cylinder for installations with
several heating circuits.
You can set the flow rate in heat pump mode. In order to do this,,
firstly make the following settings:
f
f
Temporarily remove the fuse from the electric emergency/
booster heater to isolate the emergency/booster heater from
the power supply. Alternatively, switch OFF the second heat
generator.
f
f
Operate the appliance in heating mode.
12.3.1 Minimum flow rate with individual room control by
means of FEK / FE7 in systems without buffer cylinder
For systems without a buffer cylinder: in menu „START UP“; set
parameter „B-PUMP CONST“ to „ON“.
In such cases, one or more heating circuits in the heating system
must be left open. Ensure the minimum flow rate (see „Specificati-
on / Data table“) by means of the correspondingly opened heating
circuits (see table „Design recommendation for underfloor heating
system in the lead room“).
Note
The table applies if individual room control is installed.
Sizing recommendation for the underfloor heating system in the
lead room:
minimum flow
rate
minimum water content of the
buffer cylinder or the open cir-
cuits
Composite pipework 16 x 2 mm
/ clearance 10 cm
Composite pipework 20 x 2.25 mm
/ clearance 15 cm
Lead room
floor area
Number of cir-
cuits
Lead room
floor area
Number of cir-
cuits
l/h
l
m²
n x m
m²
n x m
WPL 15 IKS
840
24
28
4x70
21
2x70
WPL 25 IK
1000
35
-
-
32
3x70
Buffer cylinder always
required
recommended buffer cylinder
volume, underfloor heating
system
recommended buffer cylinder
volume, radiators
activate the integral
emergency/booster he-
ater
WPL 15 IKS
no
100
200
yes
WPL 25 IK
no
200
400
yes
f
f
Install the open heating circuit(s) in the lead room (room
where the external programming unit of the heat pump cont-
rol unit is installed, such as in the living room). The individu-
al room can then be controlled either with the external pro-
gramming unit or indirectly by adjusting the heating curve or
the room influence.