Mitsubishi Electric PUMY-P100VHM Technical & Service Manual page 74

Header-Branch Method
Connection Examples
(Connecting to Four Indoor Units)
Total Piping Length
Permissible
Farthest Piping Length
Length
Farthest Piping Length After First Branch
Height Difference in Indoor/Outdoor Section
Permissible High/
Low Difference
Height 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,f)
Select the size from the right table.
Additional refrigerant charge
• Refrigerant of 3kg equivalent to 50m total
extended piping length is already charged
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.
A
A
B
a b
C C
A+a+b+c+d+e+f [ 120m
A+f [ 80m
(L)
(R)
f is 30 meters or less
(H) 30 meters or less (If the outdoor unit is lower, 20 meters or less)
(h)
12 meters 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 header (4 branches)
CMY-Y64-G-E
(1) Refrigerant Piping Diameter in Section
From Outdoor Unit to First Branch (Out-
door Unit Piping Diameter)
Model Piping Diameter (mm)
Liquid Line
PUMY-P100-140
Gas Line
<Additional Charge>
Additional Liquid pipe size
refrigerant charge Total length of
{9.52
=
(kg)
<Example> Outdoor : 125
Indoor 1 : 63 A : {9.52 30m
2 : 40
3 : 25
4 : 20
The total length of each liquid line is as follows
{9.52 : A + a = 30 + 15 = 45m
{6.35 : b + c + d = 10 + 10 + 20 = 40m
Therefore,
<Calculation example>
Additional
refrigerant charge = 45
74
L
r
D
c d e
c C C
Branch header (8 branches)
CMY-Y68-G-E
(2) Refrigerant Piping Diameter in Section
From Branch to Indoor Unit (Indoor Unit
Piping Diameter)
Model number
{9.52
50 or lower
{15.88
63 to 140
Liquid pipe size
Total length of
0.06 0.024
{6.35
+
(m) 0.06 (kg/m) (m) 0.024 (kg/m)
a : {9.52 15m
b : {6.35 10m
c : {6.35 10m
d : {6.35 20m
0.06 + 40 0.024 – 3.0 = 0.7kg (rounded up)
f
C
A Outdoor Unit
B First Branch
C Indoor unit
D CAP
Piping Diameter (mm)
Liquid Line {6.35
Gas Line {12.7
Liquid Line {9.52
Gas Line {15.88
Refrigerant
amount for outdoor
unit
–
3.0kg
At the conditions
below: