Daikin Altherma 3 R F EHVZ04S18E 6V Series - Formula to Calculate the Expansion Vessel Pre-Pressure; To Check the Water Volume and Flow Rate

8 | Piping installation
Installer reference guide
68
ERGA04~08EAV3(A) + EHVZ04+08S18+23EA6V+9W
Daikin Altherma 3 R F
4P629093-1 – 2020.08
▪ Domestic hot water tank – Disinfection. For the disinfection function of the
domestic hot water tank, see "10.5.6Tank"[4159].
▪ 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
▪ Valve towards expansion vessel. The valve towards the expansion vessel (if
equipped) MUST be open.
8.2.2 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)
8.2.3 To check the water volume and flow rate
The indoor unit has an expansion vessel of 10litre with a factory-set pre-pressure
of 1bar.
To make sure that the unit operates properly:
▪ You must check the minimum and maximum water volume.
▪ You might need to adjust the pre-pressure of the expansion vessel.
Minimum water volume
There are no requirements for the minimum water volume.
INFORMATION
In critical processes, or in rooms with a high heat load, extra water might be
required.
NOTICE
When circulation in each space heating/cooling loop is controlled by remotely
controlled valves, it is important that the minimum water volume is guaranteed,
even if all of the valves are closed.