Mitsubishi Electronics OC366 Air Conditioner User Manual


 
86
Method of Combined Branching of Lines and
Headers
Connection Examples
(Connecting to 5 Indoor Units)
Outdoor unit
First branching (branching
joint)
Branching joint
Indoor unit
Branching header
To downstream unit
Blind caps
A
B
C
D
E
F
G
A+B+C+a+b+c+d+e is 120 meters [394 ft] or less
A+B+b is 80 meters [262 ft] or less
B+b is 30 meters [100 ft] or less
50 meters [164 ft] or less (If the outdoor unit is lower, 20 meters [70 ft] or less)
12 meters [39 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.)
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 right table.
(1) Refrigerant Piping Diameter In Section
From Outdoor Unit to First Branch (Out-
door Unit Piping Diameter)
(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)
(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)
Refrigerant of 3kg [6.6 lbs] equivalent to 50m
[165 ft] total extended piping length is
already included when the outdoor unit is
shipped.
Thus, if the total extended piping length is
50m [165 ft] or less, there is no need to
charge with additional refrigerant.
If the total extended piping length exceeds
50m [165 ft], 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 : P48
Indoor
1 : P24 A : W9.52 [3/8"] 10 m [33 ft] a : W9.52 [3/8"] 15m [49 ft]
2 : P15 B : W9.52 [3/8"] 10 m [33 ft] b : W6.35 [1/4"] 10m [33 ft]
3 : P08 C : W9.52 [3/8"] 10 m [33 ft] c : W6.35 [1/4"] 10m [33 ft]
4 : P06 d : W6.35 [1/4"] 10m [33 ft]
5 : P06 e : W6.35 [1/4"] 10m [33 ft]
The total length of each liquid line is as follows;
W9.52 :
A + B + C + a = 10 m + 10 m + 10 m + 15 m = 45 m [33 ft + 33 ft + 33 ft + 49 ft = 148 ft]
W6.35 :
b + c + d + e = 10 m + 10 m + 10 m + 10 m = 40 m [33 ft + 33 ft + 33 ft + 33 ft = 132 ft]
<Calculation example>
Additional
refrigerant charge = 45 m × 0.06 kg + 40 m × 0.024 kg – 3.0 kg = 0.7kg (rounded up)
= [148 ft × 0.041 lbs + 132 ft × 0.016 lbs – 6.6 lbs = 1.58 lbs]
Additional
refrigerant charge
(kg)
[lbs]
Liquid pipe size
Total length of
W9.52 × 0.06 kg
[3/8" × 0.041 lbs]
(m) × 0.06 (kg/m),
[ft] × 0.041 [lbs/ft]
=
Liquid pipe size
Total length of
W6.35 × 0.024 kg
[1/4" × 0.016 lbs]
(m) × 0.024 (kg/m),
[ft] × 0.016 [lbs/ft]
+
Refrigerant
amount for outdoor
unit
3.0kg
[6.6 lbs]
At the
conditions
below:
Branch Joint
CMY-Y62-G-E
Branch Header (4 branches)
CMY-Y64-G-E
Branch Header (8 branches)
CMY-Y68-G-E
A
F
B
A
E
G
C
D
D D D
D
A
C
b
B
3
H
h
4
L
1
5
1
2
c
d e
a
Note: Pipe re-branching after the header branching
is not possible.
Note: The total of downstream unit models in the
table is the total of models as seen from point
A in the figure above.
Liquid Line
Gas Line
Piping Diameter (mm [inch])Model
PUMY-P36, 48
Liquid Line (mm [inch]) Gas Line (mm [inch])
W15.88 [5/8]W9.52 [3/8]
Liquid Line
Gas Line
Liquid Line
Gas Line
Piping Diameter (mm [inch])
Model number
18 or lower
24 to 54
W6.35 [1/4]
W12.7 [1/2]
W9.52 [3/8]
W15.88 [5/8]
W9.52 [3/8]
W15.88 [5/8]