Daikin VRV IV Series - Refrigerant Piping Material; To Select the Piping Size

16 | Piping installation
Installer and user reference guide
67
RKXYQ5T8+8T7Y1B + RDXYQ5T8+8T7V1B
VRV IV heat pump for indoor installation
4P499898-1B – 2021.12
▪ Foreign materials inside pipes (including oils for fabrication) must be
≤30mg/10m.
16.1.2 Refrigerant piping material
▪ Piping material: Phosphoric acid deoxidised seamless copper.
▪ Piping temper grade and thickness:
Outer diameter (Ø) Temper grade Thickness (t)
(a)
6.4mm (1/4")
9.5mm (3/8")
12.7mm (1/2")
Annealed (O) ≥0.80mm
t
Ø
15.9mm (5/8") Annealed (O) ≥0.99mm
19.1mm (3/4")
22.2mm (7/8")
Half hard (1/2H) ≥0.80mm
(a)
Depending on the applicable legislation and the maximum working pressure of the unit
(see "PS High" on the unit name plate), larger piping thickness might be required.
16.1.3 To select the piping size
Determine the proper size using the following tables and reference figure (only for
indication).
A
a
B
D
D
C
D
D
b
EKEXV
AHU
VRV DX
VRV DX
c
c
a Heat exchanger unit
b Compressor unit
c Refrigerant branch kit
VRVDX VRVDX indoor unit
EKEXV Expansion valve kit
AHU Air handling unit
A Piping between heat exchanger unit and compressor unit
B Piping between compressor unit and (first) refrigerant branch kit (=main pipe)
C Piping between refrigerant branch kits
D Piping between refrigerant branch kit and indoor unit
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
"16.4.3To determine the additional refrigerant amount"[483].
A: Piping between heat exchanger unit and compressor unit
Use the following diameters: