Changing The Pre-Pressure Of The Expansion Vessel; To Check The Water Volume: Examples; Preparing Electrical Wiring; About Preparing Electrical Wiring - Daikin CHYHBH05AA Installer's Reference Manual

6 Preparation
Installation
height
≤280 l
(a)
difference
≤7 m No pre-pressure
adjustment is required.
>7 m Do the following:
▪ Increase the
pressure.
▪ 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.
Example in case of a radiator application: Maximum water
volume and expansion vessel pre-pressure in case of 80°C
Installation
height
≤140 l
(a)
difference
≤7 m No pre-pressure
adjustment is required.
>7 m Do the following:
▪ Increase the
pressure.
▪ 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.
Minimum flow rate
Check that the minimum flow rate (required during defrost/backup
heater operation) in the installation is guaranteed in all conditions.
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
05+08 models
See the recommended procedure as described in
during commissioning" on page 70.
Installer reference guide
20
Water volume
>280 l
Do the following:
▪ Decrease the pre-
pressure.
▪ 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
recommended to install
NOT
an extra vessel outside
the unit.
Water volume
>140 l
Do the following:
▪ Decrease the pre-
pressure.
▪ 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
recommended to install
NOT
an extra vessel outside
the unit.
9 l/min
"10.4 Checklist
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:
▪ 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 for either underfloor heating
loops or radiators.
Example 2
The indoor unit is installed at the highest point in the water circuit.
The total water volume in the water circuit is 350 l. Radiators are
installed, so use the graph of 80°C.
Actions:
▪ Because the total water volume (350 l) is more than the default
water volume (140 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 205 l.
(See the graph in the chapter above).
▪ Because 350 l is more than 205 l, the expansion vessel is too
small for the installation. Therefore install an extra vessel outside
the installation.
6.5

Preparing electrical wiring

6.5.1

About preparing electrical wiring

INFORMATION
Also read the precautions and requirements in the
"General safety precautions" chapter.
Daikin hybrid for multi heat pump – heat pump module
a
CHYHBH05+08AA + EHYKOMB33A
4P471761-1A – 2017.10