77
11 REFRIGERANT PIPING TASKS
Line-Branch Method
Connection Examples
(Connecting to 4 Indoor Units)
Liquid Line
Gas Line
Piping Diameter (mm)Model
PUMY-P100~140
Liquid Line (mm) Gas Line (mm)
W15.88W9.52
Liquid Line
Gas Line
Liquid Line
Gas Line
Piping Diameter (mm)
Model number
50 or lower
63 to 140
W6.35
W12.7
W9.52
W15.88
Outdoor Unit
First Branch
Indoor unit
A
B
C
A+B+C+a+b+c+d 120m
A+B+C+d 80m
B+C+d 30m
30 meters or less (If the outdoor unit is lower, 20 meters or less)
12 meters or less
Use an optional branch piping kit (CMY-Y62-G-E).
Total Piping Length
Farthest Piping Length
Farthest Piping Length After First Branch
High/Low Difference in Indoor/Outdoor Section
High/Low Difference in Indoor/Indoor Section
Permissible
Length
Permissible High/
Low Difference
(L)
(1)
(H)
(h)
■ Selecting the Refrigerant Branch Kit
■ Select Each Section of Refrigerant Piping
■ Additional refrigerant charge
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)
(1) Section From Outdoor Unit
to First Branch (A)
(2) Sections From Branch to
Indoor Unit (a,b,c,d)
(3) Section From Branch to
Branch (B,C)
(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)
Each
Section of
Piping
• Refrigerant of 3kg equivalent to 50m total
extended piping length is already included
when the outdoor unit is shipped.
Thus, if the total extended piping length is
50m or less, there is no need to charge with
additional refrigerant.
• If the total extended piping length exceeds
50m, calculate the required additional
refrigerant charge using the procedure
shown on the right.
• If the calculated additional refrigerant charge
is a negative amount, do not charge with any
refrigerant.
<Additional Charge>
<Example> Outdoor model : 125
Indoor 1 : 63 A : W9.52 10m a : W9.52 15m
2 : 40 B : W9.52 10m b : W6.35 10m
3 : 25 C : W9.52 10m c : W6.35 10m
4 : 20 d : W6.35 20m
The total length of each liquid line is as follows;
W9.52 : A + B + C + a = 10 + 10 + 10 + 15 = 45m
W6.35 : b + c + d = 10 +10 + 20 = 40m
<Calculation example>
Additional
refrigerant charge = 45
× 0.06 + 40 × 0.024 – 3.0 = 0.7kg (rounded up)
Additional
refrigerant charge
(kg)
Liquid pipe size
Total length of
W9.52 × 0.06
(m) × 0.06 (kg/m)
=
Liquid pipe size
Total length of
W6.35 × 0.024
(m) × 0.024 (kg/m)
+
Refrigerant
amount for outdoor
unit
3.0kg
–
At the conditions
below:
W9.52
W15.88
A
H
B C
L
1
d
a
h
b c
11-1. REFRIGERANT PIPING SYSTEM