Installation manual
14
EKHBH/X008BA
Indoor unit for air to water heat pump system
4PW54185-1B
Water pipework
Checking the water circuit
The units are equipped with a water inlet and water outlet for
connection to a water circuit. This circuit must be provided by a
licensed technician and must comply with all relevant European and
national regulations.
Checking the water volume and expansion vessel
pre-pressure
The unit is equipped with an expansion vessel of 10 litre which has a
default pre-pressure of 1 bar.
To assure proper operation of the unit, the pre-pressure of the
expansion vessel might need to be adjusted and the minimum and
maximum water volume must be checked.
1
Check that the total water volume in the installation, excluding
the internal water volume of the indoor unit, is 10 l minimum.
Refer to
"Technical specifications" on page 39
to know the
internal water volume of the indoor unit.
2
Using the table below, determine if the expansion vessel pre-
pressure requires adjustment.
NOTE
The unit is only to be used in a closed water system.
Application in an open water circuit can lead to
excessive corrosion of the water piping.
NOTE
Before continuing the installation of the unit, check the
following points:
■
The maximum water pressure = 3 bar + static
pressure of pump.
■
The maximum water temperature is 65°C (safety
device setting).
■
Two shut-off valves are delivered with the unit. To
facilitate service and maintenance, install one at
the water inlet and one at the water outlet of the
indoor unit. Mind position of the shut-off valves.
Orientation of the integrated drain and fill valves is
important for servicing. See
■
Drain taps must be provided at all low points of
the system to permit complete drainage of the
circuit during maintenance.
Two drain valves integrated in the shut-off valves
are provided to drain the water from the indoor
unit water system.
■
Make sure to provide a proper drain for the
pressure relief valve to avoid any water coming
into contact with electrical parts.
■
Air vents must be provided at all high points of the
system. The vents should be located at points
which are easily accessible for servicing. An
automatic air purge is provided inside the indoor
unit. Check that this air purge valve is not tightened
too much so that automatic release of air in the wa-
ter circuit remains possible.
■
Take care that the components installed in the
field piping can withstand the water pressure and
water temperature.
■
Always use materials which are compatible with
water used in the system and with the materials
used on the indoor unit.
■
Select piping diameter in relation to required
water flow and available ESP of the pump.
■
The minimum required water flow for the indoor
unit operation is 12 l/min. When the water flow is
lower than this minimum value, flow error
7H
will
be displayed and the operation of the indoor unit
will be stopped.
In most applications this minimum water volume will have a
satisfying result.
In critical processes or in rooms with a high heat load
though, extra water volume might be required.
NOTE
When circulation in each space heating loop is
controlled by remotely controlled valves, it is important
that this minimum water volume is kept even if all the
valves are closed.
Example
FHL1
FHL2
FHL3
M1
T1
M2
T2
M3
T3
5
4
3
2
1
7
6
8
1
Outdoor unit
8
By-pass valve (field
supply)
2
Indoor unit
3
Heat exchanger
FHL1..3
Floor heating loop
(field supply)
4
Pump
5
Shut-off valve
T1..3
Individual room
thermostat
(optional)
6
Collector (field
supply)
M1..3
Individual
motorised valve to
control loop FHL1
(field supply)
7
Shut-off valve
