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manual
HRC
70
PILOT -PREMIUM-
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manual
HRC
70
PILOT -PREMIUM-
/2
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7
3.3.2 - Hydraulic connections :
Heat Pump circuit
3.3.3 - Heat Pump and Pilot pressure-relief
valves
3.3.4 - Desludging
A sufficient flow rate should be ensured so that the difference in
temperature between the outlet and inlet of the Heat Pump does
not exceed 5°C when the Heat Pump is operating at full power
(take a temperature measure when the HRC
70
Heat Pump is in
heating mode and the system is fully functioning).
The hydraulic connection section between the Heat Pump and
the Pilot must be sufficient.
Using the tables below, determine the minimum inner diameter
of the connecting piping needed depending on the distance
which separates the Heat Pump and the Pilot.
Heat pump model
11kW
17kW
20kW
25kW
Minimum nominal flow rate
1500 L/h 1350 L/h 1550 L/h 1850 L/h
Maximum pressure
2,5 bars
2,5 bars
2,5 bars
2,5 bars
Minimum Ø of piping
If distance* between HP and pilot < 15m
24/26
24/26
28/30
32/34
If distance* between HP and pilot < 25m
28/30
28/30
32/34
36/38
If distance* between HP and pilot < 50m
32/34
32/34
36/38
42/44
* distance consists of both outlet and inlet
Make sure that all sections of piping are equipped with functional
and accessible air valves.
The Heat Pump’s hydraulic connection to the Pilot can be made
using steel, copper, or reticulated polyethylene pipes with a
minimum equivalent diameter of 1’’.
The hydraulic kit must be installed using flexible piping on the
water inlet and outlet points of the Heat Pump in order to prevent
any vibrations from being transmitted to the heating system.
The Heat Pump and the Pilot are both equipped with pressure-
relief valves.
The pressure-relief valve on the Heat Pump sets the maximum
acceptable pressure in the installation (2.5 bars when hot). The
maximum service pressure in the Heat Pump must, consequently,
be lower than 2.5 bars.
Example : If the Heat Pump is positioned 5m below the Pilot, the
pressure reading on the Pilot would be 0.5 bars less than
the real pressure of the water in the Heat Pump. In this case,
the maximum service pressure for the Pilot would be 2 bars.
Therefore it would be advisable to fill the heating circuit at
an intermediary pressure (between 1 and 1.5 bars).
In case of operating with a back-up boiler, these pressure-relief
valves
MUST
be installed in addition to the ones which the boiler
is already equipped with.
The connections and the evacuation conduits for the pressure-
relief valves must be made from materials which are resistant to
high temperatures and corrosion.
HRC HP
Existing
boiler
PILOT
CP
: Pilot pressure gauge
S
: Pressure-relief valve for the Pilot, set at 3 bars
Sch
: Pressure-relief valve for existing boiler
SPAC : Pressure-relief valve for Heat Pump set at 2.5 bars
The HRC
70
Pilot has an integrated desludging function which
collects oxides, limescale, and other particles which may become
detached from the inner walls of the heating circuit. The lower
part of the system is equipped with a sludge valve which should
be briefly activated at least once per year (see § «Maintenance
and repairs»).
For underfloor heating installations, it is advised to install a
settling tank, which will complement the actions taken by the
Pilot.
See § «Setting the 4 speeds on the circulator pump» in the HRC
70
Heat Pump installer manual.
