Panasonic U-4..6ML5XPQ, Service Manual

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Example of Connection
Appendix 249
4. Example of Connection
Example of connection
(Connection of 8 indoor units Heat pump system) Branch with refnet joint Branch with refnet joint and refnet header Branch with refnet header
Maximum
allowable
length
Between outdoor and
indoor units
Actual pipe length
Pipe length between outdoor and indoor units 150 m
[Example] unit 8: a+b+c+d+e+f+g+p 150 m [Example] unit 6: a+b+h 150 m, unit 8: a+i+k 150 m [Example] unit 8: a+i 150 m
Equivalent length Equivalent pipe length between outdoor and indoor units 175 m (Assume equivalent pipe length of refnet joint to be 0.5 m and of the refnet header to be 1.0 m. (for calculation purposes))
Total extension
length
Total piping length from outdoor unit to all indoor units between 10 m and 300 m
Allowable
height
Between outdoor and
indoor units Difference in
height
Difference in height between outdoor and indoor units (H1) 50 m (40 m if outdoor unit is located in a lower position).
Between indoor and indoor
units Difference in
height
Difference in height between adjacent indoor units (H2) 15 m
Allowable length after the branch Actual pipe length
Pipe length from first refrigerant branch kit (either refnet joint or refnet header) to indoor unit 40 m
[Example] unit 8: b+c+d+e+f+g+p 40 m [Example] unit 6: b+h 40 m, unit 8: i+k 40 m [Example] unit 8: i 40 m
Refrigerant branch kit selection
Refrigerant branch kits can only be used with R-410A.
Use the following refnet joint Use the following refnet header
Pipe size selection
Caution on selecting connection pipes
If the overall equivalent piping length is 90 m, be sure to
enlarge the pipe diameter of the gas-side main piping. If the
recommended pipe size is not available, stick to the original
pipe diameter (which may result in a small capacity decrease).
[Gas side]
U-4..5ML5: Ø15.9.Ø19.1
U-6ML5: Ø19.1.Ø22.2
A. Piping between outdoor unit and refrigerant branch kit
• Match to the size of the connection piping on the outdoor unit.
Outdoor unit connection piping size
B. Piping between refrigerant branch kits
•
Use the pipe size from the following table.
C. Piping between refrigerant branch kit and indoor unit
• Pipe size for direct connection to indoor unit must be the same as the
connection size of indoor unit.
How to calculate the additional refrigerant to be charged
Additional refrigerant to be charged R (kg)
R should be rounded off in units of 0.1 kg
indoor unit
refnet joint
refnet header
a b c d e f g
h i j k l m n
1 2 3 4 5 6 7
8
H2
H1
p
A B C D E F G H1
H2
a
i
b
c d e f g h
1 2 3 4 5 6
k
j
7 8
A B
a
H1
H2
c d e f
g
h i b
1 2 3 4 5 6 7
8
Outdoor unit capacity type Refrigerant branch kit name
U-4..6ML5 CZ-P20BK32Q
Outdoor unit capacity type Refrigerant branch kit name
U-4..6ML5 CZ-P29HK32Q
Main pipe
(enlarge)
First refrigerant
branch kit
Indoor
unit
Outdoor unit
capacity type
Piping size (outer diameter x minimum
thickness)
Gas pipe Liquid pipe
U-4..5ML5 Ø15.9x1.0
(Ø19.1x1.0)
Ø9.5x0.8
U-6ML5 Ø19.1x1.0
(
Ø22.2x1.0)
Piping size (outer diameter x minimum thickness)
Gas pipe Liquid pipe
Ø15.9x1.0 Ø9.5x0.8
Indoor capacity
index
Piping size
(outer diameter x minimum thickness)
Gas pipe Liquid pipe
20+25+32+40+50 Ø12.7x0.8 Ø6.4x0.8
63+80+100+125 Ø15.9x1.0 Ø9.5x0.8
R=
(
Total length (m) of liquid
p
iping size at Ø9.5
)
x0.054+
(
Total length (m) of liquid
piping size at Ø
6.4
)
x0.022
Example for refrigerant branch using refnet joint and refnet header
R=[73 x 0.054] + [69 x 0.022] = 5.46 5.5 kg
a: Ø9.5x30 m d: Ø9.5x13 m g: Ø6.4x10 m j: Ø6.4x10 m
b
: Ø9.5x10 m e: Ø6.4x10 m h: Ø6.4x20 m k: Ø6.4x9 m
c: Ø9.5x10 m f: Ø6.4x10 m i: Ø9.5x10 m
Panasonic