Selection Of Piping Size - Daikin VRV RXYQ72XBYC Series Installation Manual

7.3. Selection of piping size

Determine the proper size referring to following tables and reference
figure (only for indication).
A
a x
D D
b b
E
E
1 2 3 4
1-4 VRV indoor unit
a, b Refrigerant branching kit
x, y Outdoor unit multi connection piping kit
7.3.1. Piping between outdoor units and (first) refrigerant
branch kit: A, B, C
Choose from the following table in accordance with the outdoor unit
total capacity type, connected downstream.
Piping outer diameter size
Outdoor unit capacity
type
Gas pipe
RXYQ72X type 3/4 in. (19.1 mm)
RXYQ96X type 7/8 in. (22.2 mm)
RXYQ120, 144X type
1-1/8 in. (28.6 mm)
RXYQ168-216X type
RXYQ240X type
1-3/8 in. (34.9 mm)
RXYQ264-336X type
RXYQ360-384X type 1-5/8 in. (41.3 mm)
English
B B B
C
y
Liquid pipe
3/8 in. (9.5 mm)
1/2 in. (12.7 mm)
5/8 in. (15.9 mm)
3/4 in. (19.1 mm)
7.3.2. Piping between refrigerant branch kits: D
Choose from the following table in accordance with the indoor unit
total capacity type, connected downstream. Do not let the connec-
tion piping exceed the refrigerant piping size chosen by the general
system model name.
Piping outer diameter size
Indoor unit
capacity index
Gas pipe
< 54 5/8 in. (15.9 mm)
54 ≤ × < 72
3/4 in. (19.1 mm)
72 ≤ × < 111
7/8 in. (22.2 mm)
111 ≤ × < 162
1-1/8 in. (28.6 mm)
162 ≤ × < 230
230 ≤ × < 300
1-3/8 in. (34.9 mm)
> 300 1-5/8 in. (41.3 mm)
Example:
Downstream capacity for D = capacity index of unit 1 + capacity index
of unit 2
7.3.3. Piping between refrigerant branch kit and indoor unit: E
Pipe size for direct connection to indoor unit must be the same as the
connection size of the VRV indoor unit.
Piping outer diameter size
Indoor unit
capacity index
Gas pipe
05, 07, 09, 12, 18 1/2 in. (12.7 mm)
24, 30, 36, 48, 54 5/8 in. (15.9 mm)
72 3/4 in. (19.1 mm)
96 7/8 in. (22.2 mm)
• When the equivalent pipe length between outdoor and indoor units
is 295 ft. (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 it is possible
to increase the size of the main pipes.
• Even as the length of the piping is less than 295 ft. (90 m), it is able
to increase the diameter of piping to improve performance.
1
1 Outdoor unit
2 Main pipes (outdoor unit to first refrigerant branch kit)
3 Increase
4 First refrigerant branch kit
5 Indoor unit
Liquid pipe
3/8 in. (9.5 mm)
1/2 in. (12.7 mm)
5/8 in. (15.9 mm)
3/4 in. (19.1 mm)
Liquid pipe
1/4 in. (6.4 mm)
3/8 in. (9.5 mm)
2 3 5
4
10