Changing The Pre-Pressure Of The Expansion Vessel; To Check The Water Volume: Examples - Daikin ERGA08DAV3 Installer's Reference Manual

i Collector (field supply)
j Overpressure bypass valve (delivered as accessory)
FHL1...3 Floor heating loop (field supply)
HPC1...3 Heat pump convector (field supply)
T1...3 Individual room thermostat (optional)
M1...3 Individual motorised valve to control loop FHL1...3 and
HPC1...3 (field supply)
INFORMATION
The pump of the additional zone ensures that the minimum
flow rate for correct operation of the unit is guaranteed.
Maximum water volume
Use the following graph to determine the maximum water volume for
the calculated pre-pressure.
a
2.4
2
1.5
1
0.5
0.3
20 50 100 150
a Pre-pressure (bar)
b Maximum water volume (l)
Example: Maximum water volume and expansion vessel pre-
pressure
Installation
height
≤200 l
(a)
difference
≤7 m No pre-pressure
adjustment is required.
>7 m Do the following:
▪ Increase the
pressure according to
the
installation
difference. The
pressure
increase by 0.1 bar for
each metre above 7 m.
▪ Check if the water
volume does
exceed the maximum
allowed water volume.
(a) This is the height difference (m) between the highest point
of the water circuit and the indoor unit. If the indoor unit is
at the highest point of the installation, the installation height
is 0 m.
ERGA04~08DAV3(A) + EHVZ04+08S18+23DA +
EHVZ04+08S18+23DJ
Daikin Altherma 3 R F
4P495249-1B – 2019.06
200 250 290
Water volume
>200 l
Do the following:
▪ Decrease the pre-
pressure according to
the required installation
height difference. The
pre-pressure should
decrease by 0.1 bar for
each metre below 7 m.
▪ Check if the water
volume does NOT
exceed the maximum
allowed water volume.
The expansion vessel of
the indoor unit is too
pre-
small for the installation.
In this case, it is
required
recommended to install
height
an extra vessel outside
pre-
the unit.
should
NOT
Minimum flow rate
Check that the minimum flow rate in the installation is guaranteed in
all conditions on each zone separately. This minimum flow rate is
required during defrost/backup heater operation. For this purpose,
use the overpressure bypass valve delivered with the unit.
NOTICE
When circulation in each or certain space heating loops is
controlled by remotely controlled valves, it is important that
the minimum flow rate is guaranteed, even if all valves are
closed. In case the minimum flow rate cannot be reached,
a flow error 7H will be generated (no heating or operation).
Minimum required flow rate
12 l/min
See the recommended procedure as described in
during commissioning" on
6.4.4 Changing the pre-pressure of the
expansion vessel
NOTICE
Only a licensed installer may adjust the pre-pressure of the
expansion vessel.
When changing the default pre-pressure of the expansion vessel
(1 bar) is required, take following guidelines into account:
b
▪ 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 Schrader valve
6.4.5

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.
6 Preparation
"9.4 Checklist
page 72.
a
Installer reference guide
23