Mitsubishi MLP-444WU - Page 22

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3-3. PIPE CONNECTION
• Incaseofreconnectingtherefrigerantpipesafterdetaching,makethearedpart
of pipe re-fabricated.
• Fastenarenutwithatorquewrenchasspeciedinthetable.
• Whenfastenedtootight,arenutmaybrakeafteralongperiodandcauserefriger-
ant leakage.
• Be sure to wrap insulation around the piping. Direct contact with the bare piping
may result in burns or frostbite.
Indoor unit connection
Connect both liquid and gas pipings to indoor unit.
• Apply a thin coat of refrigeration oil on the seat surface of pipe.
• Forconnection,rstalignthecenter,thentightentherst3to4turnsofarenut.
• Use tightening torque table above as a guideline for indoor unit side union joint
section,andtightenusingtwowrenches.Excessivetighteningdamagestheare
section.
Outdoor unit connection
Connect pipes to stop valve pipe joint of the outdoor unit in the same manner
applied for indoor unit.
• For tightening, use a torque wrench or spanner and use the same tightening torque
applied for indoor unit.
3-2. FLARING WORK
1) Cut the copper pipe correctly with pipe cutter. (Fig. 1, 2)
2) Completely remove all burrs from the cut cross section of pipe. (Fig. 3)
• Put the end of the copper pipe to downward direction as you remove burrs in
order to avoid to let burrs drop in the piping.
3)Remove are nuts attached to indoor and outdoor units, then put them on pipe
havingcompletedburrremoval.(Notpossibletoputthemonafteraringwork.)
4) Flaring work (Fig. 4, 5). Firmly hold copper pipe in the dimension shown in the table.
Select A inch (mm) from the table according to the tool you use.
5) Check
• ComparethearedworkwithFig.6.
• Ifareisnotedtobedefective,cutoffthearedsectionanddoaring work
again.
3-4. INSTALLING THE PIPE COVER
Make sure to install the pipe cover. Incorrect installation results in water leakage.
• No insulation is needed on the pipe connecting part of the indoor side for this unit.
The pipe cover gathers the water condensed around the pipe connecting part.
1) Install the pipe band removed in 3-1. to secure the connecting pipes.
* The pipe band should hold down the insulating material of connecting pipe. In-
sulating material should protrude 3/8 in. (10 mm) or more than the pipe band, as
shown in the illustration on the right.
2) Install pipe cover.
When using pipe with super insulating material
(about ø1-7/8 in. (ø48 mm) liquid pipe, ø2 in. (ø51 mm) gas pipe)
1) Make sure that the plate is turned over, and the concave part is facing upward.
(Refer to 3-1.)
2) Use band
provided with the unit. (Do not use the pipe band attached to the
unit)
3) Connecting pipe exit of pipe cover is precut. Cut it along the line.
4) Install pipe cover.
Note:
Install pipe cover and pipe band securely. Incomplete installation will cause water
to drip from the unit, soaking and damaging household goods.
Insulating material
should protrude 3/8 in.
(10 mm) or more than
the edge of pipe band
Pipe band
Pipe cover
Band
(accessory part)
Fixing screw
Cut
Pipe cover
Insulating material
should protrude 3/8 in.
(10 mm) or more than
the edge of pipe band
Insulating material
should protrude 3/8 in.
(10 mm) or more than
the edge of pipe band
Insulating material
should protrude 3/8 in.
(10 mm) or more than
the edge of pipe band
Fixing screw
[When using pipe with super
insulating material]
Copper
pipe
Good
90°
Tilted Uneven Burred
No good
Fig. 1 Fig. 2
Burr
Copper pipe
Spare reamer
Pipe cutter
Fig. 4Fig. 3
Smooth all
around
Even length
all around
Inside is shin-
ing without any
scratches.
Fig. 5 Fig. 6
A
Flare nut
Die
Copper pipe
Clutch type
Flaring tool
Wing nut type
When installing the unit, securely connect the refrigerant
pipes before starting the compressor.
WARNING
Pipe
diameter
inch (mm)
B inch
(mm)
A inch (mm) Tightening torque
Clutch type
tool for
R410A
Clutch type
tool for
R22
Wing nut
type tool
for R22
ft-lb
(kgf•cm)
N•m
ø1/4
(6.35)
21/32
(17)
0 to 0.02
(0 to 0.5)
0.04 to
0.06
(1.0 to 1.5)
0.06 to
0.08
(1.5 to 2.0)
10 to 13
(140 to 180)
13.7 to 17.7
ø3/8
(9.52)
7/8
(22)
25 to 30
(350 to 420)
34.3 to 41.2
ø1/2
(12.7)
1-1/32
(26)
0.08 to
0.10
(2.0 to 2.5)
36 to 42
(500 to 575)
49.0 to 56.4
ø5/8
(15.88)
1-5/32
(29)
54 to 58
(750 to 800)
73.5 to 78.4
BH79A643H01_01En.indd 9 2021/05/06 17:37:24