Selecting Pipe Size; Different-Diameter Joint (Optional Parts); Piping Preparation; Installation Procedure (2 Branches Pipe (Joint)) - Mitsubishi Electric PUMY-P112VKM1 Installation Manual

4. Installing the refrigerant piping
In case of using 1-branch box
Flare connection employed. (No. brazing)
A
B
In case of using 2-branch boxes
2 branches pipe (joint)
: optional parts.
A A
A
B B
Fig. 4-3
(1) Valve size for outdoor unit
For liquid
For gas
(2) Valve size for branch box
Liquid pipe
UNIT
Gas pipe
Liquid pipe
UNIT
Gas pipe
Liquid pipe
UNIT
Gas pipe
Liquid pipe
UNIT
Gas pipe
Liquid pipe
UNIT
Gas pipe
* 3-branch type : only , , unit
A
Fig. 4-4
8
Branch box
B B B
Branch box #1
B B
Branch box #2
ø9.52 mm
ø15.88 mm
ø6.35 mm
ø9.52 mm
ø6.35 mm
ø9.52 mm
ø6.35 mm
ø9.52 mm
ø6.35 mm
ø9.52 mm
ø6.35 mm
ø12.7 mm
Conversion formula
1/4 F ø6.35
3/8 F ø9.52
1/2 F ø12.7
B
5/8 F ø15.88
3/4 F ø19.05

4.3. Selecting pipe size

4.3.1. Connection without Branch Box
Gas side Pipe size (mm)
Liquid side Pipe size (mm)
B
4.3.2. Connection with Branch Box (Fig. 4-3)
A
The piping connection size differs according to the type
and capacity of indoor units. Match the piping connec-
Liquid (mm) ø9.52
tion 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
Gas (mm) ø15.88
branch box side. (Connect deformed joint directly to
the branch box side.)
Different-diameter joint (optional parts) (Fig. 4-4)
Connected pipes diameter
Model name
B
ø9.52 → ø12.7
MAC-A454JP
ø12.7 → ø9.52
MAC-A455JP
ø12.7 → ø15.88
MAC-A456JP
ø6.35 → ø9.52
PAC-493PI
ø9.52 → ø15.88
PAC-SG76RJ-E

Piping preparation

Table below shows the specifications of pipes commercially available.
Outside diameter Insulation thickness
mm
6.35
9.52
12.7
15.88
Ensure that the 2 refrigerant pipes are insulated to prevent condensation.
Refrigerant pipe bending radius must be 100 mm or more.
Caution:
Be sure to use the insulation of specified thickness. Excessive thickness may
cause incorrect installation of the indoor unit and branch box, and lack of
thickness may cause dew drippage.
2-branch pipe (Joint) : Optional parts (According to the connection method,
you can choose the favorite one.)
Model name
MSDD-50AR-E
MSDD-50BR-E

Installation procedure (2 branches pipe (Joint))

Refer to the installation manuals of MSDD-50AR-E and MSDD-50BR-E.
Pipe size (Outdoor unit-Branch box)
Pipe size Liquid ø9.52
(ømm) Gas ø15.88
Pipe size (Branch box-Indoor unit) *Case of M series or S series Indoor unit
Indoor
(kW) 15 20
unit type
Pipe size Liquid ø6.35 ø6.35 ø6.35 ø6.35 ø6.35 ø6.35 ø6.35 ø6.35 ø9.52 ø9.52
(ømm) Gas ø9.52 ø9.52 ø9.52 ø9.52 ø9.52 ø9.52 ø12.7 ø15.88 * ø15.88 ø15.88
* When using 60 type indoor unit of MEXZ series, use the flare nut in the
indoor unit accessory for the gas side connecting of indoor unit.
Do not use the flare nut (gas side) attached to the indoor unit. If it is used,
a gas leakage or even a pipe extraction may occur.
Pipe size (Branch box-Indoor unit) *Case of P series indoor unit
Indoor unit
*1
(kW)
35
type
Pipe size Liquid ø6.35
(ømm) Gas ø12.7
*1 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.
*2 For details about connecting the pipes for the P100 indoor unit, refer to the
installation manual of the Y-shape connection pipe (PAC-AK52YP-E).
Indoor unit
15-50 63-140
ø12.7 ø15.88
ø6.35 ø9.52
B
Diameter A
mm mm
ø9.52
ø12.7
ø12.7
ø6.35
ø9.52
Insulation material
mm
8
8 Heat resisting foam plastic
0.045 specific gravity
8
8
Connection method
flare
brazing
The lineup of a connectable indoor unit
depends on a district/areas/country.
22 25 35 42 50 60
*1
50 60 71
ø6.35 ø9.52 ø9.52
ø12.7 ø15.88 ø15.88
Outdoor unit
112-140
ø15.88
ø9.52
Diameter B
mm
ø12.7
ø9.52
ø15.88
ø9.52
ø15.88
71 80
*2
100
ø9.52
ø15.88