Daikin Altherma 3 GEO Series - Formula to Calculate the Expansion Vessel Pre-Pressure; To Check the Water Volume and Flow Rate of the Space Heating Circuit and Brine Circuit

7 | Piping installation
Installer reference guide
67
EGSAH/X06+10UDA9W
Daikin Altherma 3 GEO
4P598592-1A – 2019.12
▪ Thermostatic mixing valves. In accordance with the applicable legislation, it may
be necessary to install thermostatic mixing valves.
▪ Hygienic measures. The installation must be in compliance with the applicable
legislation and may require additional hygienic installation measures.
▪ Recirculation pump. In accordance with the applicable legislation, it may be
required to connect a recirculation pump in between the hot water end point
and the recirculation connection of the domestic hot water tank.
c
d
a b
a Recirculation connection
b Hot water connection
c Shower
d Recirculation pump
7.1.2 Formula to calculate the expansion vessel pre-pressure
The pre-pressure (Pg) of the vessel depends on the installation height difference
(H):
Pg=0.3+(H/10) (bar)
7.1.3 To check the water volume and flow rate of the space heating circuit and brine circuit
The unit does not have an integrated expansion vessel, but a field supplied
expansion vessel can be installed in the brine circuit in case installing the brine
level vessel (delivered as accessory) is not optimal. For more information, see
"7.2.4To connect the brine level vessel"[469].
To make sure that the unit operates properly:
▪ You must check the minimum water volume.
▪ You might need to adjust the pre-pressure of the expansion vessel.
▪ You must check the total space heating water volume in the unit.
▪ You must check the total brine water volume in the unit.
Minimum water volume
Check that the total water volume per circuit in the installation is minimum 20litre,
the internal water volume of the indoor unit NOT included.
INFORMATION
If a minimum heating load of 1 kW can be guaranteed and setting [4.B] Space
heating/cooling > Overshoot (overview field setting [9‑04]) is 4°C, the
minimum water volume can be lowered to 10litre.
INFORMATION
In critical processes, or in rooms with a high heat load, extra water might be
required.