To Select Refrigerant Branch Kits - Daikin VRV IV Q+ Series Installer And User Reference Manual

18 | Piping installation

18.1.4 To select refrigerant branch kits

Installer and user reference guide
74
▪ 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
31.8
34.9
38.1+41.3
(a)
If annealed temper grade is 1.
The refrigerant pipes and branches must meet the condition of design pressure
33 bar (3.3 MPa). If it is NOT possible to confirm this, use the refrigerant branch as
mentioned in this chapter.
Confirm that the pipe thickness complies with the required minimum thickness.
▪ 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 the additional refrigerant amount.
Refrigerant refnets
For piping example, refer to
▪ 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
24~42
▪ 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
Minimal thickness t (mm)
"To select the piping size" [
0.4
0.5
0.7
0.9
(a)
0.6
0.6
0.8
0.9
1.0
1.1
4
72].
2 pipes
KHRQ22M29T9
KHRQ22M64T
KHRQ22M75T
2 pipes
KHRQ22M20T
KHRQ22M29T9
RXYQQ8~20U7Y1B
VRV IV Q+ series heat pump
4P546229-1A – 2020.10