
INSTALLATION
Commissioning
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The design of the underfloor heating system determines the pos-
sible flow rate through the permanently open heating circuits.
If the flow rate of the permanently open heating circuits is less
than the minimum flow rate of the heat pump, check whether the
available external delivery head of the heating circulation pump
is sufficient.
Delivery head test
ΔpUP* ≥ (Vmin / VHKo)² × (ΔpHK + ΔpV) + ΔpWP
ΔpUP External delivery head of the circulation pump at Vmin
* If the circulation pump is integrated in an indoor unit, the
available external head can be found in the specification
for the indoor unit.
Vmin Minimum flow rate of heat pump
VHKo Design flow rate of the permanently open heating circuits
ΔpHK Design pressure drop of the permanently open heating
circuits
ΔpVDesign pressure drop to and from floor distributors
ΔpWP Pressure drop in the heat pump at Vmin
For heat pumps with an integral circulation pump, the pressure
drop of the heat pump (ΔpWP) is not taken into account.
If the external delivery head is not sufficient for the minimum flow
rate, additional heating circuits for the underfloor heating must
be permanently opened.
Checking the minimum flow rate
The setting is made in heat pump mode. In order to do this, firstly
make the following settings:
f Temporarily remove the fuse from the electric emergency/
auxiliary heater to isolate the emergency/auxiliary heater
from the power supply. Alternatively, switch OFF the second
heat generator.
f Ensure that hydronic balancing has been performed.
f Check the connected pumps against the hydraulic diagram.
12.2.2 Systems without a buffer cylinder
Note
If the appliance is operated solely through the WPM heat
pump manager, and an external pump that is not con-
trolled by the WPM is used as a heating circuit pump, you
will have to adjust the heating circuit pump manually.
For systems without a buffer cylinder, one or more heating cir-
cuits in the system must remain open. The open heating circuit(s)
must be installed in the lead room (room in which the external
programming unit is installed, e.g. living room or bathroom). The
lead room can be individually controlled using the external pro-
gramming unit, or indirectly by adjusting the heating curve or
activating room influence.
f Operate the appliance in heating mode.
f When designing underfloor heating in the lead room, ob-
serve our recommendations. The table applies if individual
room control is installed.
HPA-O 3
CS Plus
HPA-O 4
CS Plus
HPA-O 6
CS Plus
HPA-O 8
CS Plus
Minimum flow rate of heat pump
l/h 400 400 600 600
Minimum water content of the open heating circuits during
operation without buffer cylinder
l16 16 19 19
Composite pipework 16 x 2mm / installation spacing 10cm
Lead room floor area
m² 21 21 21 21
Number of circuits
nxm 3x70 3x70 3x70 3x70
Composite pipework 20 x 2.25mm / installation spacing 15cm
Lead room floor area
m² 21 21 21 21
Number of circuits
nxm 2x70 2x70 2x70 2x70
Buffer cylinder always required
No No No No
Buffer cylinder volume in relation to product range
l80-200 80-200 80-200 80-400
Activate the integral emergency/auxiliary heater
Yes Yes Yes Yes
f Fully open the heating circuit(s) in the lead room.
f Close all other heating circuits.
f If an overflow valve is installed in the heating system, close
this valve.
f Adjust the parameters.
Parameter Setting
MINIMUM PUMP RATE (COMMISSIONING/ CHARGING
PUMP CONTROL / STANDBY/ TYPE OF CONTROL)
OFF
MAXIMUM PUMP RATE (COMMISSIONING/ CHARGING
PUMP CONTROL / STANDBY/ TYPE OF CONTROL)
ON
f Check the current flow rate.
Parameter
WP WATER FLOW RATE (INFO/ HEAT PUMP/ PROCESS DATA)
f Compare the value with the minimum flow rate (see chapter
"Specification/ Data table").
Minimum flow rate has been reached
No further measures required.
f Reset the parameters to their original values.
Parameter Setting
MINIMUM PUMP RATE (COMMISSIONING/ CHARGING
PUMP CONTROL / STANDBY/ TYPE OF CONTROL)
ON
MAXIMUM PUMP RATE (COMMISSIONING/ CHARGING
PUMP CONTROL / STANDBY/ TYPE OF CONTROL)
OFF
Minimum flow rate has not been reached
If the specified flow rate is not met, take suitable measures to
achieve the flow rate.
f Open the heating circuit permanently in another room.
f Check the current flow rate.
f If the minimum flow rate is not reached, repeat these steps.
f Set the overflow valve correctly.