Daikin EPRA18DAV3 Installer's Reference Manual page 76

7 | Piping installation
Installer reference guide
76
▪ 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 minimum 20 litres, the
internal water volume of the outdoor unit NOT included.
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.
c
c
c
a Individual room thermostat (optional)
b Overpressure bypass valve (delivered as accessory)
c Shut-off valve
Maximum water volume
NOTICE
The maximum water volume depends on whether glycol is added to the water
circuit. For more information on the addition of glycol, refer to
circuit against
Use the following graph to determine the maximum water volume for the
calculated pre-pressure.
A
2,4
2,1
1,8
1,5
1,2
1
0,9
0,6
0,3
20 70
A Pre-pressure (bar)
B Maximum water volume (l)
Water
Water + glycol
Example: Maximum water volume and expansion vessel pre-pressure
c
c
M1 M2
a a
4
freezing" [ 82].
120 170 200 220
140
b
M3
a
"To protect the water
270 320
B
EPRA14~18DAV3+W1 + ETVH/X16S18+23DA6V+9W(G)
Daikin Altherma 3 H HT F
4P587502-1B – 2020.12