To Select The Piping Size - Daikin RWEYQ8T9Y1B Installation And Operation Manual

4 Preparation
▪ All piping lengths and distances have been taken into
consideration (see About the piping length in the installer
reference guide).
▪ 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
6.4 mm/9.5 mm/12.7 mm
15.9 mm
19.1 mm/22.2 mm
28.6 mm
34.9 mm
41.3 mm
▪ 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 18.
4.2.2

To select the piping size

INFORMATION
Please select the proper pipe sizes depending on the
mode of your system. There are 2 possible modes:
▪ heat pump,
▪ heat recovery.
Determine the proper size using the following tables and reference
figure (only for indication).
In case of heat pump mode
A
a x
D F
b 3
G
E
1 2 4 5
1,2 VRV DX indoor unit
3 BP box
4,5 RA DX indoor unit
a,b Indoor branch kit
x,y Outdoor multi connection kit
Installation and operation manual
8
Minimal thickness t
0.80 mm
0.99 mm
0.80 mm
0.99 mm
1.21 mm
1.43 mm
B B B
C
y
In case of heat recovery mode
A
a x
D E
3 4
b
E
1 2
1,2 VRV DX indoor unit
3 BS unit
4 Cooling only VRV indoor unit
A~E Piping
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.
In case of heat pump mode
Outdoor unit Piping outer diameter size (mm)
capacity type (HP)
Gas pipe
8
10
12~16
18~22
24
26~34
36~42
In case of heat recovery mode
Outdoor unit Piping outer diameter size (mm)
capacity type (HP)
Liquid pipe
5~8 9.5
10
12 12.7
14~16
18 15.9
20~22
24
26~34 19.1
36
38~42
D: Piping between refrigerant branch kits or
refrigerant branch kit and BS unit
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.
VRV IV water-cooled system air conditioner
B B B
C
y
Liquid pipe
19.1 9.5
22.2
28.6 12.7
15.9
34.9
19.1
41.3
Suction gas High
pipe pressure/low
pressure gas
pipe
19.1 15.9
22.2 19.1
28.6
22.2
28.6
34.9
41.3
34.9
RWEYQ8~14T9V1B+RWEYQ8~14T9Y1B
4P452190-1A – 2017.04