5 Preparation
Installer and user reference guide
14
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546228-1 – 2018.09
3
BP box
4,5
RA DX indoor unit
a,b
Indoor branch kit
x,y
Outdoor multi connection kit
A, B, C: Piping between outdoor unit and (first)
refrigerant branch kit
Choose from the following table in accordance with the outdoor unit
total capacity type, connected downstream.
Outdoor unit
capacity type (HP)
Piping outer diameter size (mm)
Gas pipe
Liquid pipe
8
19.1
9.5
10
22.2
9.5
12~16
28.6
12.7
18~22
28.6
15.9
24
34.9
15.9
26~34
34.9
19.1
36~54
41.3
19.1
D: Piping between refrigerant branch kits
Choose from the following table in accordance with the indoor unit
total capacity type, connected downstream. Do not let the
connection piping exceed the refrigerant piping size chosen by the
general system model name.
Indoor unit capacity
index
Piping outer diameter size (mm)
Gas pipe
Liquid pipe
<150
15.9
9.5
150≤x<200
19.1
200≤x<290
22.2
290≤x<420
28.6
12.7
420≤x<640
15.9
640≤x<920
34.9
19.1
≥920
41.3
Example:
▪ Downstream capacity for E=capacity index of unit 1
▪ Downstream capacity for D=capacity index of unit 1+capacity
index of unit 2
E: Piping between refrigerant branch kit and
indoor unit
Pipe size for direct connection to indoor unit must be the same as
the connection size of the indoor unit (in case indoor unit is VRV DX
indoor or Hydrobox).
Indoor unit capacity
index
Piping outer diameter size (mm)
Gas pipe
Liquid pipe
15~50
12.7
6.4
63~140
15.9
9.5
200
19.1
250
22.2
▪ When the equivalent pipe length between outdoor and indoor
units is 90 m or more, the size of the main pipes (both gas side
and liquid side) must be increased. Depending on the length of the
piping, the capacity may drop, but even in such a case the size of
the main pipes has to be increased. More specifications can be
found in the technical engineering data book.
a
e
b
c
d
a
Outdoor unit
b
Main pipes
c
Increase if the equivalent piping length is ≥90 m
d
First refrigerant branch kit
e
Indoor unit
Size up
HP class
Piping outer diameter size (mm)
Gas pipe
Liquid pipe
8
19.1 → 22.2
9.5 → 12.7
10
22.2 → 25.4
(a)
12+14
28.6
(b)
12.7 → 15.9
16
28.6 → 31.8
(a)
18~22
15.9 → 19.1
24
34.9
(b)
26~34
34.9 → 38.1
(a)
19.1 → 22.2
36~54
41.3
(b)
(a)
If the size-up size is NOT available, you must use the
standard size. Sizes bigger than the size-up size are NOT
allowed. But even if you use the standard size, the
equivalent piping length is allowed to be more than 90 m.
(b)
Pipe size-up is NOT allowed.
▪ The pipe thickness of the refrigerant piping shall comply with the
applicable legislation. The minimal pipe thickness for R410A
piping must be in accordance with the table below.
Pipe Ø (mm)
Minimal thickness t (mm)
6.4/9.5/12.7
0.80
15.9
0.99
19.1/22.2
0.80
28.6
0.99
34.9
1.21
41.3
1.43
▪ In case the required pipe sizes (inch sizes) are not available, it is
also allowed to use other diameters (mm sizes), taken the
following into account:
▪ Select the pipe size nearest to the required size.
▪ Use the suitable adapters for the change-over from inch to mm
pipes (field supply).
▪ The additional refrigerant calculation has to be adjusted as
mentioned in
"6.7.3 To determine the additional refrigerant
F: Piping between refrigerant branch kit and BP
unit
Pipe size for direct connection on BP unit must be based on the total
capacity of the connected indoor units (only in case RA DX indoor
units are connected).
Total capacity index
of connected indoor
units
Piping outer diameter size (mm)
Gas pipe
Liquid pipe
20~62
12.7
6.4
63~149
15.9
9.5
150~208
19.1
Example:
Downstream capacity for F=[capacity index of unit 4]+[capacity index
of unit 5]
