Installing The Refrigerant Piping - Mitsubishi Electric City Multi PKFY-P NHMU-E2 Série Manuel D'installation

4. Installing the refrigerant piping

B
A
45°±2°
Fig. 4-1
A Flare cutting dimensions
Copper pipe O.D. Flare dimensions
(mm, inch) øA dimensions (mm, inch)
ø6.35, 1/4" 8.7 - 9.1, 11/32 - 23/64
ø9.52, 3/8" 12.8 - 13.2, 1/2 - 33/64
ø12.7, 1/2" 16.2 - 16.6, 41/64 - 21/32
ø15.88, 5/8" 19.3 - 19.7, 49/64 - 25/32
Liquid pipe
Tightening
Pipe size O.D.
torque.
(mm, inch)
(N·m, ft·lbs)
P08, ODø6.35 14 - 18
P12, 1/4" 10 - 13
P15
ODø9.52 14 - 18*
P18
3/8" 10 - 13
* Connect the joint with the following pipes: Liquid and gas pipes of P18.
E Apply refrigerating machine oil over the entire flare seat surface.
PKFY-P·NHMU-E2
D
1-11/16
25/32
B
Fig. 4-3
6
(inch)
C
R22
Gas pipe
Tightening
Pipe size O.D.
torque.
(mm, inch)
(N·m, ft·lbs)
ODø12.7 49 - 61
1/2" 35 - 44
ODø15.88 49 - 61*
5/8" 35 - 44
35-23/64
21-7/32
17-63/64
( C )
24-1/64
F F
2-13/64
Fig. 4-2
A
4.1. Connecting pipes (Fig. 4-1)
• When commercially available copper pipes are used, wrap liquid and gas pipes
with commercially available insulation materials (heat-resistant to 100 °C, 212 °F
or more, thickness of 12 mm, 1/2 inch or more).
• The indoor parts of the drain pipe should be wrapped with polyethylene foam
insulation materials (specific gravity of 0.03, thickness of 9 mm, 23/64 inch or
D
more).
• Apply thin layer of refrigerant oil to pipe and joint seating surface before
tightening flare nut.
• Use two wrenches to tighten piping connections.
• Use refrigerant piping insulation provided to insulate indoor unit connections.
Insulate carefully.
B Refrigerant pipe sizes & Flare nut tightening torque
C Do not apply refrigerating machine oil to the screw portions.
(This will make the flare nuts more apt to loosen.)
D Be certain to use the flare nuts that are attached to the main unit.
(Use of commercially-available products may result in cracking.)
R410A
Liquid pipe
Tightening
Pipe size O.D.
torque.
(mm, inch)
(N·m, ft·lbs)
ODø6.35 14 - 18
1/4" 10 - 13
ODø6.35 14 - 18
1/4" 10 - 13
( B ) 6-7/32
1-11/16
( A )
6-21/32
7-7/32
1-27/32
2-23/64 5-5/16
4.2. Positioning refrigerant and drain piping (Fig. 4-2)
PKFY-P·NHMU-E2
A Gas pipe * Indicates the condition with accessories mounted.
B Liquid pipe
C Drain hose
D Left-side piping knockout hole
Right-side piping knockout hole
E
Lower piping knockout hole
F
G Mount board 1
4.3. Refrigerant piping (Fig. 4-3)
Indoor unit
1. Remove the flare nut and cap of the indoor unit.
2. Make a flare for the liquid pipe and gas pipe and apply refrigerating machine oil
(available from your local supplier) to the flare sheet surface.
3. Quickly connect the on site cooling pipes to the unit.
4. Wrap the pipe cover that is attached to the gas pipe and make sure that the
connection join is not visible.
5. Wrap the pipe cover of the unit's liquid pipe and make sure that it covers the
insulation material of the on site liquid pipe.
6. The portion where the insulation material is joined is sealed by taping.
A Site-side refrigerant piping
B Unit side refrigerant piping
Gas pipe
Tightening
Pipe size O.D. Liquid pipe
torque.
(mm, inch) (mm, inch)
(N·m, ft·lbs)
ODø12.7 49 - 61
1/2" 35 - 44 43/64
ODø12.7 49 - 61
1/2" 35 - 44 43/64
(inch)
G
E
Flare nut O.D.
Gas pipe
(mm, inch)
17 26
1-1/16
17 26
1-1/16