Daikin Altherma 3 R F, Installer'S Reference Manual

Page: 108 / 312

8 | Piping installation
Installer reference guide
108
ERLA11~W1 + EBVH16SU23DJ
Daikin Altherma 3 R F
4P655196-1 – 2021.09
8.5.2 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)
8.5.3 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…
Heating operation 20 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.
M2
a
b
a a
c
c
M3 M1
a Individual room thermostat (option)
b Overpressure bypass valve (delivered as accessory)
c Shut-off valve (delivered as accessory)
M1...3 Individual motorised valve to control each loop (field supply)
Maximum water volume
Use the following graph to determine the maximum water volume for the
calculated pre-pressure.