Daikin Altherma 3 H MT F, Installer'S Reference Manual

Page: 70 / 276

8 | Piping installation
Installer reference guide
70
EPRA08~W1 + ET9W
Daikin Altherma 3 H MT F
4P634887-1 – 2021.03
▪ 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
8.1.2 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)
8.1.3 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
Check that the total water volume in the installation is higher than the minimum
water volume, the internal water volume of the indoor unit NOT included:
If… Then the minimum water volume
is…
Cooling operation 20 l
Heating operation 0 l
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.