Daikin VRV IV RYYQ10T7Y1B Series - 4.2.3 To select refrigerant branch kits; E: Piping between refrigerant branch kit and indoor unit; F: Piping between refrigerant branch kit and BP unit; G: Piping between BP unit and RA DX indoor unit

4 Preparation
Installation and operation manual
8
RYYQ+RYMQ+RXYQ8~20T7Y1B
VRV IV system air conditioner
4P370473-1C – 2016.07
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 "5.6.3 To determine the additional refrigerant
amount"on page17.
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
G: Piping between BP unit and RA DX indoor unit
Only in case RADX indoor units are connected.
Indoor unit capacity
index
Piping outer diameter size (mm)
Gas pipe Liquid pipe
20, 25, 30 9.5 6.4
50 12.7
60 9.5
71 15.9
4.2.3 To select refrigerant branch kits
INFORMATION
When using FXTQ indoor units, different requirements
apply. See "4.2.4 Requirements in case of FXTQ indoor
units"on page9.
Refrigerant refnets
For piping example, refer to "4.2.2 To select the piping size" on
page7.
▪ 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).