Daikin HXHD125A7V1B, Installation Manual

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Installation manual
16
HXHD125A7V1B
VRVIII system indoor unit
4PW62584-1A – 11.2010
2 Fix the top panel on the unit with the appropriate screws.
3 Stick the top plate insulation (accessory) at the inside of the top
decoration panel according to the figure below.
4 Fix the top decoration panel on top
of the unit using the appropriate
screws. In case a domestic hot
water tank (optional) is installed,
refer to the domestic hot water tank
installation manual.
5 Fix the front and remaining side decoration panel(s) back to the
unit using the appropriate screws.
7.5. Leak test and vacuuming drying R410A circuit
When the indoor unit was powered on before all brazing and
refrigerant piping work was finished on R410A side, a special setting
needs to be applied to open all valves before vacuuming can start.
See also the installation manual of the outdoor unit for furter details
and
"11.3. Vacuuming/recovery and maintenance on refrigerant side"
on page 43 .
7.6. Water piping
The unit is equipped with a water inlet and water outlet for connection
to a water circuit. This circuit must be provided by an installer and
must comply with the applicable legislation.
Checking the water volume and expansion vessel
pre-pressure
The expansion vessel in the unit avoids that the pressure in the
system increases due to temperature differences.
The unit is equipped with a 7 l expansion vessel for which the
pre-pressure can be changed (default pre-pressure is 1 bar).
Changing the pre-pressure of the expansion vessel might be needed
if the water volume of the system is too big in relation with the needed
leaving water temperature.
Refer to the graph below.
4x
5 mm
1 2
3 4
2x
2x
NOTICE
The unit is only to be used in a closed water system.
Application in an open water circuit can lead to excessive
corrosion of the water piping.
For precautions about the design of the water circuit, refer
to
"6. Design of the water circuit" on page 7 .
80°C water temperature
65°C water temperature
35°C water temperature
Never change the pre-pressure of the system to a value
lower than 0.3 bar
A Pre-pressure (bar)
B System water volume (l)
20
0.00
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400
A
B