Daikin Altherma 3 GEO Series Installer's Reference Manual page 28

7 Piping installation
NOTICE
In case of plastic pipes, make sure they are fully oxygen
diffusion tight according to DIN 4726. The diffusion of
oxygen into the piping can lead to excessive corrosion.
▪ Circuit types. Except for the refrigerant circuit, inside the unit 2
other circuits are included. For future references: the circuit
connected to the bore hole is referred to as the brine circuit, the
other circuit connected to the heating emitters is referred to as the
space heating circuit.
▪ Connecting piping – Legislation. Make all piping connections in
accordance with the applicable legislation and the instructions in
the "Installation" chapter, respecting the water inlet and outlet.
▪ Connecting piping – Force. Do NOT use excessive force when
connecting the piping. Deformation of the piping can cause
malfunctioning of the unit.
▪ Connecting piping – Tools. Only use appropriate tooling to
handle brass, which is a soft material. If NOT, pipes will get
damaged.
▪ Connecting piping – Air, moisture, dust. If air, moisture or dust
gets into the circuit, problems may occur. To prevent this:
▪ Only use clean pipes
▪ Hold the pipe end downwards when removing burrs.
▪ Cover the pipe end when inserting it through a wall, to prevent
dust and/or particles from entering the pipe.
▪ Use a decent thread sealant to seal connections.
▪ Closed circuit. Use the indoor unit ONLY in a closed water
system for brine circuit and space heating circuit. Using the
system in an open water system will lead to excessive corrosion.
WARNING
When connecting to an open groundwater system, an
intermediate heat exchanger is required to prevent
damage (dirt, freeze ups) to the unit.
▪ Expansion vessel – Water side. To avoid cavitation, install an
expansion vessel (field supply) on the entering pipe before the
water pump within 10 m of the unit.
▪ Glycol. For safety reasons, it is NOT allowed to add any kind of
glycol to the space heating circuit.
▪ Piping length. It is recommended to avoid long runs of piping
between the domestic hot water tank and the hot water end point
(shower, bath,...) and to avoid dead ends.
▪ Piping diameter. Select the piping diameter in relation to the
required flow and the available external static pressure of the
pump. See "16 Technical data"
pressure curves of the indoor unit.
▪ Fluid flow. Depending on the type of operation, the minimum
required flow can be different. See
volume and flow rate of the space heating circuit and brine
circuit" [ 4 29] for more information.
▪ Field supply components – Fluid. Only use materials that are
compatible with fluid used in the system and with the materials
used in the indoor unit.
▪ Field supply components – Fluid pressure and temperature.
Check that all components in the field piping can withstand the
fluid pressure and fluid temperature.
▪ Fluid pressure – Space heating and brine circuit. The
maximum fluid pressure of the space heating and brine circuit is
3 bar.
▪ Fluid pressure – Domestic hot water tank. The maximum fluid
pressure of the domestic hot water tank is 10 bar. Provide
adequate safeguards in the water circuit to ensure that the
maximum pressure is NOT exceeded.
Installer reference guide
28
[ 4 98] for the external static
"7.1.3 To check the water
▪ Fluid temperature. All installed piping and piping accessories
(valve, connections,...) MUST
temperatures:
INFORMATION
The following illustration is an example and might NOT
match your system layout.
65°C
70°C
▪ Drainage – Low points. Provide drain taps at all low points of the
system in order to allow complete drainage of the circuit.
▪ Drainage – Pressure relief valve. Connect the drain hose
properly to the drain to avoid water dripping out of the unit. See
"6.3.4 To connect the drain hose to the
▪ Zn-coated parts. NEVER use Zn-coated parts in the fluid circuit.
Because the unit's internal circuit uses copper piping, excessive
corrosion may occur. Zn-coated parts used in the brine circuit may
lead to the precipitation of certain components in the anti-freeze
fluids corrosion inhibitor.
WARNING
Due to presence of glycol, corrosion of the system is
possible. Uninhibited glycol will turn acidic under the
influence of oxygen. This process is accelerated by the
presence of copper and high temperatures. The acidic
uninhibited glycol attacks metal surfaces and forms
galvanic corrosion cells that cause severe damage to the
system. Therefore it is important that:
▪ the water treatment is correctly executed by a qualified
water specialist,
▪ a glycol with corrosion inhibitors is selected to
counteract acids formed by the oxidation of glycols,
▪ no automotive glycol is used because their corrosion
inhibitors have a limited lifetime and contain silicates
which can foul or plug the system,
▪ galvanized pipes are NOT used in glycol systems since
the presence may lead to the precipitation of certain
components in the glycol's corrosion inhibitor.
withstand the following
drain" [ 4 27].
EGSAH/X06+10DA9W(G)
Daikin Altherma 3 GEO
4P569820-1A – 2019.09