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Connecting the water circuit
Water connections must be made in accordance with local
regulations and the outlook diagram delivered with the unit,
respecting the water in- and outlet.
Be careful not to deform the unit piping by using excessive
force when connecting the piping. Deformation of the
piping can cause the unit to malfunction.
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.
The sealing must be able to withstand the pressures and
temperatures of the system.
When using non-brass metallic piping, make sure to insulate
both materials from each other to prevent galvanic corrosion.
Because
brass
is
material, use appropriate tooling
for connecting the water circuit.
Inappropriate tooling will cause
damage to the pipes.
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.
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.
Preferably choose a ball type 3-way valve 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 recommended maximum changeover time of
the valve should be less than 60 seconds.
Protecting the water circuit against freezing
Frost can cause damage to the hydraulic system. As this unit is
installed outdoors and thus the hydraulic system is exposed to
freezing temperatures, care must be taken to prevent freezing of the
system.
All hydraulic parts are insulated to reduce heat loss. Insulation must
be foreseen on the field piping.
The unit is already equipped with several features to prevent freezing.
The software contains special functions using pump and back
up heater to protect the complete system against freezing.
This function will only be active when the unit is off.
Only for EDL and EBL units:
As extra safety, a heatertape is winded around the piping to
protect vital parts of the hydraulic system inside the unit.
This heatertape will only be active in case of an abnormal
situation concerning the pump and will only protect internal parts
of the unit. It can not protect field installed parts outside the unit.
Field heater tape must be foreseen by the installer.
However in case of power failure, above mentioned features can not
protect the unit from freezing.
E(D/B)(H/L)Q011~016BA6V3+W1
Unit for air to water heat pump system
4PW57621-1A
a
soft
If power failure can happen at times the unit is unattended, Daikin
recommends adding glycol to the water system. Refer to
"Use of glycol" on page
16.
Refer to
"[4-04] Freeze protection function" on page
Depending on the expected lowest outdoor temperature, make sure
the water system is filled with a weight concentration of glycol as
mentioned in the table below.
Minimum outdoor temperature
–5°C
–10°C
–15°C
–20°C
–25°C
WARNING
(a)
ETHYLENE GLYCOL IS TOXIC
(b)
The concentrations mentioned in the table above will
not prevent the medium from freezing, but prevent the
hydraulics from bursting.
(c)
The maximum allowed water volume is then reduced
according to the
volume" on page
Caution: "Use of glycol"
Caution: Use of glycol
For installations with a domestic hot water tank, the
use
of
propylene
inhibitors, is only allowed if classified as Category 3
according to EN1717 or equivalent based on national
regulations.
In case of over-pressure when using glycol, be sure to
connect the safety valve to a drain pan in order to
recover the glycol.
For this purpose a knock out hole is foreseen in the
backplate of the unit making it possible to connect a
drain pipe to the safety valve.
Connecting a drain pipe is not required if no glycol is
used. The discharged water is then drained via the
bottom of the unit.
Corrosion of the system due to presence of glycol
Uninhibited glycol will turn acidic under the influence of
oxygen. This process is accelerated by presence of copper
and at higher temperatures. The acidic uninhibited glycol
attacks metal surfaces and forms galvanic corrosion cells
that cause severe damage to the system.
It is therefore of extreme importance:
that the water treatment is correctly executed by a
qualified water specialist;
that a glycol with corrosion inhibitors is selected to
counteract acids formed by the oxidation of glycols;
that in case of an installation with a domestic hot
water tank, only the use of propylene glycol, including
necessary
inhibitors
according to EN1717 or equivalent based on national
regulations is allowed. In other installations the use of
ethylene glycol is permitted as well;
that no automotive glycol is used because their
corrosion inhibitors have a limited lifetime and contain
silicates which can foul or plug the system;
that galvanized piping is not used in glycol systems
since its presence may lead to the precipitation of
certain components in the glycol's corrosion inhibitor;
that it has to be made sure the glycol is compatible
with the used materials in the system.
31.
(a)(b)(c)
Glycol
10%
15%
20%
25%
30%
figure "Maximum allowed water
15.
glycol,
including
necessary
classified
as
Category 3
Installation manual
Caution:
16
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