Daikin VRV IV+ Installation And Operation Manual page 19

Size up
HP class Piping outer diameter size (mm)
Gas pipe
(b)
12+14 28.6
16 28.6 → 31.8
18~22
(b)
24 34.9
26~34 34.9 → 38.1
(b)
36~54 41.3
(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)
6.4/9.5/12.7
15.9
19.1/22.2
28.6
34.9
41.3
▪ 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 "To determine
amount" [ 4 25].
F: Piping between refrigerant branch kit and
branch selector box (BP box)
Pipe size for direct connection on branch selector box (BP*) must be
based on the total capacity of the connected indoor units (only in
case RA DX indoor units are connected).
Total capacity index Piping outer diameter size (mm)
of connected indoor
Gas pipe
units
20~62
63~149
150~208
Example:
Downstream capacity for F=[capacity index of unit 4]+[capacity index
of unit 5]
G: Piping between branch selector box (BP box)
and RA DX indoor unit
Only in case RA DX indoor units are connected.
Indoor unit capacity Piping outer diameter size (mm)
index
Gas pipe
20, 25, 30
50
60
71
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ heat pump
4P546220-1C – 2020.10
Liquid pipe
12.7 → 15.9
(a)
15.9 → 19.1
(a)
19.1 → 22.2
Minimal thickness t (mm)
0.80
0.99
0.80
0.99
1.21
1.43
the additional refrigerant
Liquid pipe
12.7 6.4
15.9 9.5
19.1
Liquid pipe
9.5 6.4
12.7
9.5
15.9
14.1.3 To select refrigerant branch kits
Refrigerant refnets
For piping example, refer to "To select the piping
▪ When using refnet joints at the first branch counted from the
outdoor unit side, choose from the following table in accordance
with the capacity of the outdoor unit (example: refnet joint a).
Outdoor unit capacity type
(HP)
8+10
12~22
24~54
▪ For refnet joints other than the first branch (example refnet joint b),
select the proper branch kit model based on the total capacity
index of all indoor units connected after the refrigerant branch.
Indoor unit capacity index
<200
200≤x<290
290≤x<640
≥640
▪ Concerning refnet headers, choose from the following table in
accordance with the total capacity of all the indoor units connected
below the refnet header.
Indoor unit capacity index
<200
200≤x<290
290≤x<640
≥640
(a) If the pipe size above the refnet header is Ø34.9 or more,
KHRQ22M75H is required.
INFORMATION
Maximum 8 branches can be connected to a header.
▪ How to choose an outdoor multi connection piping kit. Choose
from the following table in accordance with the number of outdoor
units.
Number of outdoor units
2
3
The RYYQ22~54 models, consisting of two or three RYMQ modules,
require a 3-pipe system. There is an additional equalising pipe for
such modules (in addition to the conventional gas and liquid piping).
This equalising pipe does not exist for RYYQ8~20 or RXYQ8~54
units.
The equalising pipe connections for the different RYMQ modules are
mentioned in below table.
RYMQ Equalising pipe Ø (mm)
8
10~16
18+20
Deciding the equalising pipe diameter:
▪ In case of 3 multi units: the connection diameter of outdoor to
T‑joint has to be kept.
▪ In case of 2 multi units: the connection pipe has to have the
largest diameter.
There is never a connection of the equalising pipe with the indoor
units.
Example: (free multi combination)
14 Piping installation
size" [ 4 18].
2 pipes
KHRQ22M29T9
KHRQ22M64T
KHRQ22M75T
2 pipes
KHRQ22M20T
KHRQ22M29T9
KHRQ22M64T
KHRQ22M75T
2 pipes
KHRQ22M29H
(a)
KHRQ22M64H
KHRQ22M75H
Branch kit name
BHFQ22P1007
BHFQ22P1517
19.1
22.2
28.6
Installation and operation manual
19