13 Piping installation
Installation and operation manual
22
LREN8~12A7 + LRNUN5A7
CO
₂
ZEAS outdoor unit and capacity up unit
4P704141-1B – 2022.12
a
b
c
a
Refrigeration indoor unit
b
Riser piping close to the indoor unit (liquid pipe)
c
Oil trap
13.1.4
To select the piping size
Determine the proper size using the following tables and reference
figure (only for indication).
2
A
B
C
D
G
J
j
f
F
E
H3
H2
H1
e
d
g
c
a
b
1
3
4
4
3
H3
1
Capacity up unit (LRNUN5*)
2
Outdoor unit (LREN* )
3
Indoor unit (showcase)
4
Indoor unit (blower coil)
A~J
Liquid piping
a~g
Gas piping
H1~H3
Height difference
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).
▪ Calculate the amount of refrigerant as described in
determine the refrigerant amount"
Piping size between outdoor unit and first branch
Model
Piping outer diameter size (mm)
(a)
K65
Liquid side
(b)
Gas side
(b)
LREN8*
Ø15.9×t1.05
Ø19.1×t1.30
LREN10*
Ø15.9×t1.05
Ø19.1×t1.30
LREN12*
Ø15.9×t1.05
Ø22.2×t1.50
(a)
For refrigeration piping (A, B, a, b).
(b)
For low load restrictions, see 'Constraints for refrigeration' in the
Installer and user reference guide.
Piping size between branching areas or between
first and second branch
Indoor unit
capacity index
(kW)
Piping outer
diameter size
(mm)
Piping material
Liquid pipe for medium temperature and low temperature
(a)
x≤3.0
Ø6.4×t0.8
C1220T–O
3.0<x≤10.0
Ø9.5×t0.65
K65 and equivalent piping
10.0<x≤18.0
Ø12.7×t0.85
K65 and equivalent piping
18.0<x
Ø15.9×t1.05
K65 and equivalent piping
Gas pipe for medium temperature
(a)
x≤6.5
Ø9.5×t0. 56
K65 and equivalent piping
6.5<x≤14.0
Ø12.7×t0.85
K65 and equivalent piping
14.0<x≤19.0
Ø15.9×t1.05
K65 and equivalent piping
19.0<x≤23.0
Ø19.1×t1.30
K65 and equivalent piping
23.0<x
Ø22.2×t1.50
K65 and equivalent piping
Gas pipe for low temperature
(a)
x≤3.0
Ø9.5×t0.65
K65 and equivalent piping
3.0<x≤6.0
Ø12.7×t0.85
K65 and equivalent piping
6.0<x≤10.0
Ø15.9×t1.05
K65 and equivalent piping
10.0<x≤13.0
Ø19.1×t1.30
K65 and equivalent piping
13.0<x
Ø22.2×t1.50
K65 and equivalent piping
(a)
Piping between branching areas (C, D, c, d)
Piping size from branch to indoor unit
Liquid and gas piping: outer diameter size
(a)
Same size as C, D, c, d.
If piping sizes of the indoor units are different, connect a reducer
close to the indoor unit to align piping sizes.
(a)
Piping from branch to indoor unit (C, D, E; c; d; e)
Piping size of spun pipes with stop valves
Liquid side
(a)
Gas side
(a)
Ø15.9×t2.0
Ø22.2×t2.1
(a)
Reducers (field supply) may be required to connect the piping.
Piping size of spun pipes for safety valves
Piping type
Size (mm)
Liquid side
Ø19.1×t2.0
13.1.5
To select refrigerant branch kits
Always use K65 T-joints with a suitable design pressure for
refrigerant branching.
13.1.6
To select expansion valves for
refrigeration
The system controls liquid temperature and liquid pressure. Select
the expansion valves as indicated according to nominal conditions
and design pressure.
Nominal conditions
The following nominal conditions are valid for the liquid piping at the
outlet of the outdoor unit. They are based on an ambient
temperature of 32°C and an evaporate temperature of –10°C or –
35°C.
Evaporate temperature
–10°C
–35°C
If showcases or blower coils are connected directly
