24
OCH634C
7-3-2. Connection with Branch box
■ In case of using 1-branch box
Flare connection employed. (No. brazing)
■ In case of using 2-branch boxes
(1) Valve size for outdoor unit
For liquid
ø9.52 mm
For gas
ø19.05 mm
(2) Valve size for branch box
A
UNIT
Liquid pipe
ø6.35 mm
Gas pipe
ø9.52 mm
B
UNIT
Liquid pipe
ø6.35 mm
Gas pipe
ø9.52 mm
C
UNIT
Liquid pipe
ø6.35 mm
Gas pipe
ø9.52 mm
D
UNIT
Liquid pipe
ø6.35 mm
Gas pipe
ø9.52 mm
E
UNIT
Liquid pipe
ø6.35 mm
Gas pipe
ø12.7 mm
Note: 3-branch type : only
A
,
B
,
C
unit
A
B
B
B
B
B
Branch box
L
A
B
Conversion formula
1/4 F
ø6.35 mm
3/8 F
ø9.52 mm
1/2 F
ø12.7 mm
5/8 F
ø15.88 mm
3/4 F
ø19.05 mm
Figure 7-2
Figure 7-3
A (Outside)
B (Inside)
Selecting size
A
B
Liquid
(mm)
L
[
20 m ø9.52 The piping connection size differs
according to the type and capacity
of indoor units.
Match the piping connection size of
branch box with indoor unit.
If the piping connection size of
branch box does not match the
piping connection size of indoor
unit, use optional different diameter
(deformed) joints to the branch box
side. (Connect deformed joint direct-
ly to the branch box side.)
L > 20 m ø12.7
Gas
(mm)
ø19.05
L: The farthest piping length for the main pipes from the outdoor
unit to the branch box.
• The line-up of a connectable indoor unit depends on a district/
areas/country.
■ Pipe size (Branch box–Indoor unit)
Case of M series or S series indoor unit
Indoor
unit type
(kW)
15 - 42
50
60
71
(BTU) 09 - 13
18
24
26
Pipe size
(ømm)
Liquid
ø6.35
ø6.35
ø9.52
Gas
ø9.52 ø12.7 ø15.88 ø15.88
■ Pipe size (Branch box–Indoor unit) Case of P series indoor unit
Indoor
unit type
(kW)
35 – 50
60 – 100
(BTU)
18
24, 30
Pipe size
(ømm)
Liquid
ø6.35
ø9.52
Gas
ø12.7
ø15.88
Note: When using 35, 50 type indoor unit of P series, use the flare
nut attached to the indoor unit.
Do not use the flare nut in the indoor unit accessory. If it is
used, a gas leakage or even a pipe extraction may occur.
Different-diameter joint (optional parts) (Figure 7-2)
Model name Connected pipes diameter Diameter A Diameter B
mm
mm
mm
MAC-A454JP
ø9.52 → ø12.7
ø9.52
ø12.7
MAC-A455JP
ø12.7 → ø9.52
ø12.7
ø9.52
MAC-A456JP
ø12.7 → ø15.88
ø12.7
ø15.88
PAC-493PI
ø6.35 → ø9.52
ø6.35
ø9.52
PAC-SG76RJ-E
ø9.52 → ø15.88
ø9.52
ø15.88
PAC-SG75RJ-E
ø15.88 → ø19.05
ø15.88
ø19.05
Different-diameter (deformed) joint (Figure 7-3)
Model name Connected pipes diameter
Outside
diameter A
Inside
diameter B
mm
mm
mm
PAC-SG78RJB-E
ø9.52 → ø12.7
ø9.52
ø12.7
PAC-SG79RJB-E
ø12.7 → ø9.52
ø12.7
ø9.52
PAC-SG80RJB-E
ø12.7 → ø15.88
ø12.7
ø15.88
PAC-SG77RJB-E
ø6.35 → ø9.52
ø6.35
ø9.52
PAC-SG76RJB-E
ø9.52 → ø15.88
ø9.52
ø15.88
PAC-SJ72RJB-E
ø15.88 →ø19.05
ø15.88
ø19.05
2-branch pipe (Joint): Optional parts (According to the
connection method, you can choose the favorite one.)
Model name
Connection method
MSDD-50AR-E
flare
MSDD-50BR-E
brazing
■ Installation procedure
Refer to the installation manual of optional parts.
A
A
A
B
B
B
B
B
Branch box #1
2 branches pipe (joint)
: optional parts.
Branch box #2
L
Figur
e 7-1
