10-1. REFRIGERANT PIPING SYSTEM
123
OCH675E
10
REFRIGERANT PIPING TASKS
Line-Branch Method
Connection Examples
(Connecting to 4 Indoor Units)
Permissible
Length
Total Piping Length
A+B+C+a+b+c+d
[
150 m
Farthest Piping Length
(L)
A+B+C+d
[
80 m
Farthest Piping Length
After First Branch
(
R
) B+C+d
[
30 m
Permissible
High/Low
Difference
High/Low Difference in
Indoor/Outdoor Section
(H)
50 meters or less (If the outdoor unit is lower, 40 meters or less)
High/Low Difference in
Indoor/Indoor Section
(h)
15 meters or less
■ Selecting the Refrigerant Branch Kit
Use an optional branch piping kit (CMY-Y62-G-E).
■ Select Each Section of Refrigerant
Piping
(1) Section From Outdoor
Unit to First Branch (A)
Each
Section of
Piping
(2) Sections From Branch to
Indoor Unit (a,b,c,d)
(3) Section From Branch to
Branch (B,C)
Select the size from the table to the right.
(1) Refrigerant Piping Diameter In Section
From Outdoor Unit to First Branch(Outdoor
Unit Piping Diameter)
Model
Piping Diameter (mm)
Liquid pipe
Gas pipe
L
[
60m
ø9.52
ø19.05
L > 60m
ø12.7
(3) Refrigerant Piping Diameter In Section
From Branch to Branch
(2) Refrigerant Piping Diameter In Section
From Branch to Indoor Unit (Indoor Unit
Piping Diameter)
Model number
Piping Diameter (mm)
–
50
Liquid Line
ø6.35
Gas Line
ø12.7
63
–
140
Liquid Line
ø9.52
Gas Line
ø15.88
200
Liquid Line
ø9.52
Gas Line
ø19.05
Note: When connecting the CONNECTION KIT (PAC-LV11M-J) and an M-series indoor unit,
refer to the installation manual for the CONNECTION KIT when selecting the pipe size and
piping length.
■ Additional refrigerant charge
Refrigerant for the extended piping is not
included in the outdoor unit when the unit
is shipped from the factory.
Therefore, charge each refrigerant piping
system with additional refrigerant at the
installation site. In addition, in order to
carry out service, enter the size and
length of each liquid pipe and additional
refrigerant charge amounts in the spaces
provided on the “Refrigerant amount”
plate on the outdoor unit.
Calculation of additional refrigerant
charge
• Calculate the additional charge using the
liquid pipe size and length of the extended
piping and total capacity of connected
indoor units.
• Calculate the additional refrigerant charge
using the procedure shown to the right,
and charge with the additional refrigerant.
• For amounts less than 0.1 kg, round
up the calculated additional refrigerant
charge.
(For example, if the calculated charge is
6.01 kg, round up the charge to 6.1 kg.)
<Additional Charge>
Calculation of refrigerant charge
Pipe size
Liquid pipe
ø6.35 mm
+
Pipe size
Liquid pipe
ø9.52 mm
+
Pipe size
Liquid pipe
ø12.7 mm
+
Total capacity of
connected indoor units
Amount for the
indoor units*
–
16.0 kW
2.5 kg
(m) × 19.0 (g/m)
(m) × 50.0 (g/m)
(m) × 92.0 (g/m)
16.1
–
25.0 kW
3.0 kg
25.1
–
29.1 kW
3.5 kg
*When connecting 4 PEFY-P
·
VMA3 indoor units, use 3.5kg regardless of the amount indicated in
the preceding table according to the total capacity.
Included refrigerant amount when shipped from the factory
Included refrigerant amount: 7.3 Kg
<Example>
Outdoor model: P200
Indoor
1: P125 (14.0 kW)
2: P40 (4.5 kW)
3: P25 (2.8 kW)
4: P20 (2.2 kW)
The total length of each liquid line is as follows:
ø9.52 : A + a = 30 + 15 = 45 m
ø6.35 : b + c + d = 10 + 10 + 20 = 40 m
The total capacity of connected indoor unit is as follows:
14.0 + 4.5 + 2.8 + 2.2 = 23.5
<Calculation example>
Additional refrigerant charge
A : ø9.52 mm 30 m
a : ø9.52 mm 15 m
b : ø6.35 mm 10 m
c : ø6.35 mm 10 m
d : ø6.35 mm 20 m
At the conditions
below:
40 × + 45 × + 3.0 = 6.1kg (rounded up)
1000
1000
19.0
50.0
Total capacity
of indoor units
Liquid pipe
(mm)
Gas pipe
(mm)
– 16.0kW
L
[
60m
ø9.52
ø15.88
L > 60m
ø12.7
16.1 – 29.1kW
L
[
60m
ø9.52
ø19.05
L > 60m
ø12.7
Outdoor Unit
First Branch
Indoor unit
A
B
C
B
A
A
H
B
C
L
R
d
a
h
b
c
C
C
C
C