EKHBH/X008BB
Indoor unit for air to water heat pump system
4PW62570-1A – 01.2011
Installation manual
16
■
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 water 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.
If air, moisture or dust gets in the water circuit, problems may occur.
Therefore, always take into account the following when connecting
the water circuit:
■
Use clean pipes only.
■
Hold the pipe end downwards when removing burrs.
■
Cover the pipe end when inserting it through a wall so that no
dust and dirt enter.
■
Use a good thread sealant for the sealing of the connections.
■
When using non-brass metallic piping, make sure to insulate
both materials from each other to prevent galvanic corrosion.
■
Because brass is a soft material, use appropriate tooling for
connecting the water circuit. Inappropriate tooling will cause
damage to the pipes.
■
Select piping diameter in relation to required water flow and
available external static pressure 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.
■
Never use Zn-coated parts in the water circuit. Excessive
corrosion of these parts may occur as copper piping is used in
the unit's internal water circuit.
■
When using a 3-way valve in the water circuit.
It is very important to guarantee full separation between
domestic hot water and floor heating water circuit.
■
When using a 3-way valve or a 2-way valve in the water circuit,
the maximum change over time of the valve shall be less than
60 seconds.
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
"12. Technical specifications" on page 50
internal water volume of the indoor unit.
(1)
2
Using the table below, determine if the expansion vessel pre-
pressure requires adjustment.
NOTICE
It is strongly recommended to install an additional filter on
the heating water circuit. Especially to remove metallic
particles from the field heating piping, it is advised to use a
magnetic or cyclone filter which can remove small
particles. Small particles can damage the unit and will not
be removed by the standard filter of the heat pump unit.
(1) When the unit is configured for restricted power supply condition mode,
INFORMATION
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.
NOTICE
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
1
Outdoor unit
2
Indoor unit
3
Heat exchanger
4
Backup heater
5
Pump
6
Shut-off valve
7
Collector (field supply)
8
By-pass valve (field supply)
FHL1...3
Floor heating loop
T1...3
Individual room thermostat (optional)
M1...3
Individual motorised valve to control the floor
heating loop (field supply)
FHL1
FHL2
FHL3
M1
T1
M2
T2
M3
T3
8
6
4
5
3
2
1
6
7
