Mitsubishi PUMY-P60NKMU Technical & Service Manual page 105

Method of Combined Branching of Lines and
Headers
Connection Examples
(Connecting to 5 Indoor Units)
Total Piping Length
Permissible
Farthest Piping Length
Length
Farthest Piping Length After First Branch
High/Low Difference in Indoor/Outdoor Section
Permissible High/
Low Difference
High/Low Difference in Indoor/Indoor Section
■
Selecting the Refrigerant Branch Kit
■
Select Each Section of Refrigerant Piping
(1) Section From Outdoor Unit
to First Branch (A)
(2) Sections From Branch to
Indoor Unit (a,b,c,d,e)
(3) Section From Branch to
Branch (B,C)
Select the size from the right table.
■
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.
• 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
32.92 kg, round up the charge to 33.0 kg.)
OCH502C
A
Note: Pipe re-branching after the header branching
is not possible.
A
B
B
C
1
A+B+C+a+b+c+d+e is 150 meters [492 ft] or less
(L)
A+B+b is 80 meters [262 ft] or less
( )
B+b is 30 meters [100 ft] or less
(H) 50 meters [164 ft] or less (If the outdoor unit is lower, 40 meters [131 ft] or less)
(h)
15 meters [49 ft] or less
Please select branching kit, which is sold separately, from the table below.
(The kit comprises sets for use with liquid pipes and for use with gas pipes.)
Branch Joint
CMY-Y62-G-E
(1) Refrigerant Piping Diameter In Section
From Outdoor Unit to First Branch (Out-
door Unit Piping Diameter)
Model Piping Diameter (mm [inch])
Liquid Line
PUMY-P60
Gas Line
(3) Refrigerant Piping Diameter In Section
From Branch to Branch
Liquid Line (mm [inch])
9.52 [3/8]
<Additional Charge>
Additional Liquid pipe size
refrigerant charge Total length of
9.52 × 0.07 kg
=
[3/8" × 0.047 lbs]
(kg) (m) × 0.07 (kg/m),
[lbs] [ft] × 0.047 [lbs/ft]
<Calculation example>
Outdoor model : P60
Indoor
1 : P24 A : 9.52 [3/8"] 10 m [33 ft]
2 : P15 B : 9.52 [3/8"] 10 m [33 ft]
3 : P08 C : 9.52 [3/8"] 10 m [33 ft]
4 : P06
5 : P06
The total length of each liquid line is as follows;
9.52 : A + B + C + a = 10 m + 10 m + 10 m + 15 m = 45 m [33 ft + 33 ft + 33 ft + 49 ft = 148 ft]
6.35 : b + c + d + e = 10 m + 10 m + 10 m + 10 m = 40 m [33 ft + 33 ft + 33 ft + 33 ft = 132 ft]
The total capacity of connected indoor units is as follows:
24 + 15 + 08 + 06 + 06 = 59
Therefore, the additional refrigerant
charge is as follows = 45 m × 0.07 kg + 40 m × 0.027 kg + 2.5 kg = 6.8 kg (rounded up)
= [147 ft × 0.047 lbs + 132 ft × 0.018 lbs + 5.5 lbs = 14.8 lbs]
105
Note: The total of downstream unit models in the
table is the total of models as seen from point
A in the figure above.
C E
A
G
c d e
3 4 5
D D D
L
b
a 2
D D
Branch Header (4 branches) Branch Header (8 branches)
CMY-Y64-G-E
(2) Refrigerant Piping Diameter In Section
From Branch to Indoor Unit (Indoor Unit
Piping Diameter)
Model number
9.52 [3/8]
18 or lower
19.05 [3/4]
24 to 54
72
Gas Line (mm [inch])
19.05 [3/4]
Liquid pipe size
Total length of
6.35 × 0.027 kg
+
+
[1/4" × 0.018 lbs]
(m) × 0.027 (kg/m),
[ft] × 0.018 [lbs/ft]
a : 9.52 [3/8"] 15m [49 ft]
b : 6.35 [1/4"] 10m [33 ft]
c : 6.35 [1/4"] 10m [33 ft]
d : 6.35 [1/4"] 10m [33 ft]
e : 6.35 [1/4"] 10m [33 ft]
F
A Outdoor unit
B First branching (branching
joint)
C Branching joint
D Indoor unit
E Branching header
F To downstream unit
G Blind caps
CMY-Y68-G-E
Piping Diameter (mm [inch])
Liquid Line 6.35 [1/4]
Gas Line 12.7 [1/2]
Liquid Line 9.52 [3/8]
Gas Line 15.88 [5/8]
Liquid Line 9.52 [3/8]
Gas Line 19.05 [3/4]
Total capacity of Amount for the
connected indoor indoor units
units
~P42 2.0kg [4.4lbs]
P43 ~ P60 2.5kg [5.5lbs]
3.0kg [6.6lbs]
P61~
At the
conditions
below: