Mitsubishi Electric City Multi PMFY-P20VBM-E Installation Manual page 5

3. Refrigerant pipe and drain pipe
A
45°±2°
Fig. 3-2
B Refrigerant pipe sizes & Flare nut tightening torque
Liquid pipe
Tightening
Pipe size
(mm)
P20/25/32/40 ODø6.35 (1/4")
ODø9.52 (3/8")
P50
P63/80 ODø9.52 (3/8")
P100/125 ODø9.52 (3/8")
* Use the provided flare nut for the following pipes: Liquid pipe of P50, P100 P125, and gas pipe of P50.
E F
D
D
G
1
Max. 20m
0.75–1.5m
N
A
B
2
K
B
E D
D
F
F
H
I
B
C
B
R407C or R22
Gas pipe
Tightening
Pipe size
torque torque
(mm)
(N.m) (N.m)
14 - 18 ODø12.7 (1/2") 49 - 61
34 - 42* ODø15.88 (5/8") 68 - 82*
34 - 42 ODø15.88 (5/8") 68 - 82
34 - 42 ODø19.05 (3/4") 100 - 120*
C
C
I
H
A·B
Fig. 3-3
C
Max. 15cm
O
J
F
L
M
D
F
G
Fig. 3-4
3.2. Connecting pipes (Fig. 3-2)
• When commercially available copper pipes are used, wrap liquid and gas pipes
with commercially available insulation materials (heat-resistant to 100 °C or more,
thickness of 12 mm or more).
• The indoor parts of the drain pipe should be wrapped with polyethylene foam insu-
lation materials (specific gravity of 0.03, thickness of 9 mm or 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. Insu-
late carefully.
A Flare cutting dimensions
Copper pipe O.D.
(mm) øA dimensions (mm)
ø6.35
ø9.52
ø12.7
ø15.88
ø19.05
R410A
Liquid pipe
Tightening
Pipe size Pipe size
torque
(mm)
(N.m)
ODø6.35 (1/4") 14 - 18 ODø12.7 (1/2")
ODø6.35 (1/4") 34 - 42 ODø12.7 (1/2")
ODø9.52 (3/8") 34 - 42 ODø15.88 (5/8")
ODø9.52 (3/8") 34 - 42 ODø15.88 (5/8")
C Apply refrigerating machine oil over the entire flare seat surface.
Installing procedures (Fig. 3-3)
1. Remove the flare nuts and caps from the indoor unit.
2. Flare-cut the liquid and gas pipes then apply refrigerating machine oil (to be lo-
cally procured) over the flare-cut seat surface.
3. Quickly connect the refrigerant piping.
∗ Remember to tighten the flare nuts with a double spanner.
4. Slide the supplied pipe cover 3 over the gas piping until it is pressed against the
sheet metal inside the unit.
5. Slide the provided pipe cover 3 over the liquid piping until it is pressed against
the sheet metal inside the unit.
6. Tighten the pipe cover 3 at the both ends (15 - 20 mm) with the supplied bands
4.
A Gas piping
B Liquid piping
C Band 4
D Pipe cover 3
3.3. Drainage piping work (Fig. 3-4)
• Use O. D. ø26 mm PVC TUBE for drain piping and provide 1/100 or more down-
ward slope.
• Be sure to connect the piping joints using adhesive of polyvinyl chloride family.
• Observe the figure for piping work.
• Use attached drain hose to change the pipe extraction direction.
1 Correct piping
2 Wrong piping
A Insulation (9 mm or more)
B Downward slope (1/100 or more)
C Support metal
Grouped piping
D VP-20 (O. D. ø26 PVC TUBE)
E Make it as large as possible
F Indoor unit
G Make the piping size large for grouped pip-
ing.
Flare dimensions
8.7 - 9.1
12.8 - 13.2
16.2 - 16.6
19.3 - 19.7
22.9 - 23.3
Flare nut O.D.
Gas pipe
Tightening Liquid
torque
pipe
(mm)
(N.m) (mm)
49 - 61 17
68 - 82
22
68 - 82 22
100 - 120 22
E Turn the seam upward.
F Press the pipe cover against the sheet metal.
G Refrigerant piping heat insulating material
H Wrap tightly
I Cut off excess length of band.
K Air bleeder
L Raised
M Odor trap
N Make as little as possible
O Make as great as possible (approx. 10 cm)
H Downward slope (1/100 or more)
I O. D. ø38 PVC TUBE for grouped piping.
(9 mm or more insulation)
J Up to 50 cm
Gas
pipe
(mm)
26
29
29
36
5