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5 Preparation
Installer and user reference guide
16
RWEYQ8~1 RWEYQ8~14T9Y1B
VRV IV water-cooled system air conditioner
4P452191-1 – 2017.04
Term
Definition
Distance
H1
Height difference between
outdoor and indoor units
50/40 m
(b)
H2
Height difference between
indoor units
15 m
30 m
(c)
H3
Height difference between
outdoor units
5 m
H4
Height difference between
outdoor unit and BP unit.
40 m
H5
Height difference between BP
units
15 m
H6
Height difference between BP
unit and RA DX indoor unit
5 m
H7
Height difference between
EKEXV-kits and AHU units
5 m
(a)
If the system capacity is a multi outdoor installation, re-read
"the first outdoor branch as seen from the indoor unit".
(b)
The allowable height difference is 50 m in case the outdoor
unit is positioned higher than the indoor unit, and 40 m in
case the outdoor unit is positioned lower than the indoor
unit.
(c)
If the outdoor unit is connected to VRV DX indoor units
only, the height difference between indoor units (H2) can
be increased to 30 m. In all other cases, the H2 is limited to
15 m.
If
Then
The outdoor unit is
positioned higher than
the indoor units
▪ Minimum connection ratio: 80%
▪ Size up the liquid piping (refer to
"5.3.2 To select the piping size" on
page 13
for more information)
▪ Activate the outdoor unit setting. Refer to
the service manual for more information.
The outdoor unit is
positioned lower than
the indoor units
▪ Minimum
connection
ratio
varies
according to the height difference
between outdoor and indoor units:
▪ 40~60 m: 80%
▪ 60~65 m: 90%
▪ 65~80 m: 100%
▪ 80~90 m: 110%
▪ Size up the liquid piping (refer to
"5.3.2 To select the piping size" on
page 13
for more information)
▪ Activate the outdoor unit setting. Refer to
the service manual for more information.
▪ No technical cooling
5.3.5
Single outdoor units and standard multi-
outdoor-unit combinations
In case of heat pump mode
Connection with VRV DX indoor units and air handling units
a
4
H1
H2
H3
H2
H7
H2
a
b
b
c
d
6
2
5
1
3
a
Outdoor unit
b
VRV DX indoor unit
c
EKEXV kit
d
Air handling unit
Pipe
Maximum length
(actual/equivalent)
Longest pipe from the outdoor unit or the
last multi-outdoor piping branch (1+2+6,
1+3, 1+2+5)
165 m/190 m
(a)
Longest pipe after the first branch (3, 2+6,
2+5)
40 m/—
In case of a multi-outdoor setup: longest
pipe from the outdoor unit to the last multi-
outdoor piping branch (4)
10 m/13 m
Total pipe length (1+2+3+4+5+6)
300 m/—
(a)
If the equivalent piping length is more than 90 m, size up
the main liquid piping according to