Mitsubishi Electric BDT CITY MULTI, Installation And Pre-Commissioning Booklet

Page: 23 / 68

23
PUMY-P-V(Y)KM-A(-BS)
129
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
Blind caps
A
B
C
D
E
F
A+B+C+a+b+c+d+e is 300 meters or less
A+B+b is 150 meters or less
B+b is 30 meters or less
50 meters or less (If the outdoor unit is lower, 40 meters or less)
15 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.)
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)
(
R
)
(H)
(h)
■
Selecting the Refrigerant Branch Kit
■
Select Each Section of Refrigerant Piping
Select the size from the table to the right.
(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)
Each
Section of
Piping
Branch Joint
CMY-Y62-G-E
Branch Header (4 branches)
CMY-Y64-G-E
Branch Header (8 branches)
CMY-Y68-G-E
■
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
+
Pipe size
Liquid pipe
+
Total capacity of
connected indoor units
Amount for the
indoor units
ø6.35 ø9.52
~ 8.0 kW 1.5 kg
(m) × 19.0 (g/m) (m) × 50.0 (g/m)
8.1 ~ 16.0 kW 2.5 kg
16.1 kW ~ 3.0 kg
Included refrigerant amount when shipped from the factory
50 ×
19.0
+ 65×
50.0
+ 3.0 = 7.2 kg (rounded up)
1000 1000
<Example>
Outdoor model : P140
Indoor 1 : P63 (7.1 kW) A : ø9.52 30 m
ø9.52 10 m
:
a : ø9.52 15 m
2 : P40 (4.5 kW) B
ø9.52 10 m
: C
b : ø6.35 10 m
3 : P25 (2.8 kW) c : ø6.35 10 m
4 : P20 (2.2 kW) d : ø6.35 20 m
5 : P20 (2.2 kW) e : ø6.35 10 m
The total length of each liquid line is as follows:
ø9.52 : A + B + C + a = 65 m
ø6.35 : b + c + d +e =50 m
The total capacity of connected indoor unit is as follows:
7.1 + 4.5 + 2.8 + 2.2+ 2.2 = 18.8
<Calculation example>
Additional refrigerant charge
At the conditions
below:
Included refrigerant amount: 4.8 kg
B
A
E
F
C
D
D D D
D
A
C
b
B
3
H
h
4
L
R
5
1
2
c
d e
a
Note: Pipe re-branching after the header branching
is not possible.
Liquid Line
Gas Line
Piping Diameter (mm) Model
Liquid Line (mm) Gas Line (mm)
{
15.88
{
9.52
Liquid Line
Gas Line
Liquid Line
Gas Line
Piping Diameter (mm) Model number
50 or lower
63 to 140
{
6.35
{
12.7
{
9.52
{
15.88
{
9.52
{
15.88
PUMY-P112
PUMY-P125
PUMY-P140
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.
OCH549