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Piping installation
Installer reference guide
81
ERLA EHFZ03S18DJ3V
Daikin Altherma 3 R F
4P596821-1B – 2021.10
The default pre-pressure of the expansion vessel is 1 bar. When it is required to
change the pre-pressure, take following guidelines into account:
▪
Only use dry nitrogen to set the expansion vessel pre-pressure.
▪
Inappropriate setting of the expansion vessel pre-pressure will lead to
malfunction of the system.
Changing the pre-pressure of the expansion vessel should be done by releasing or
increasing nitrogen pressure through the Schrader valve of the expansion vessel.
a
a
Schrader valve
8.5.5 To check the water volume: Examples
Example 1
The indoor unit is installed 5 m below the highest point in the water circuit. The
total water volume in the water circuit is 100 l.
No actions or adjustments are required.
Example 2
The indoor unit is installed at the highest point in the water circuit. The total water
volume in the water circuit is 250 l.
Actions:
▪
Because the total water volume (250 l) is more than the default water volume
(200 l), the pre-pressure must be decreased.
▪
The required pre-pressure is:
Pg = (0.3+(H/10)) bar = (0.3+(0/10)) bar = 0.3 bar
▪
The corresponding maximum water volume at 0.3 bar is 290 l. (See the graph in
▪
Because 250 l is lower than 290 l, the expansion vessel is appropriate for the
installation.
8.6 Connecting water piping
8.6.1 About connecting the water piping
Before connecting the water piping
Make sure the outdoor and indoor unit are mounted.
