Mitsubishi Electric MXZ-2C20NA4 Manual De Instalación página 6

3. FLARING WORK AND PIPE CONNECTION
3-1. PRECAUTIONS FOR DEVICES THAT USE R410A REFRIGERANT
• U se C1220 copper phosphorus, for copper and copper alloy seamless pipes, to connect the refrigerant pipes. Use refrigerant pipes with the thicknesses specified
in the table to the below. Make sure the insides of the pipes are clean and do not contain any harmful contaminants such as sulfuric compounds, oxidants, debris,
or dust.
Always apply no-oxidation brazing when brazing the pipes, otherwise, the compressor will be damaged.
When installing, relocating, or servicing the unit, make sure that no substance other than the specified refrigerant (R410A) enters the refrigerant circuit.
Any presence of foreign substance such as air can cause abnormal pressure rise and may result in explosion or injury. The use of any refrigerant other
than that specified for the system will cause mechanical failure, system malfunction, or unit breakdown. In the worst case, this could lead to a serious
impediment to securing product safety.
Pipe size (mm) ø6.35 ø9.52 ø12.7 ø15.88 ø19.05 ø22.2 ø25.4 ø28.58
Thickness (mm) 0.8
• D o not use pipes thinner than those specified above.
• Use 1/2 H or H pipes if the diameter is 19.05 mm or larger.
• B e sure to have appropriate ventilation in order to prevent ignition. Furthermore, be sure to carry out fire prevention measures that there are no dangerous or flam-
mable objects in the surrounding area.
3-2. FLARING WORK
en
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)
• Aim the copper pipe downward while removing burrs to
prevent burrs from dropping in the pipe.
3) Remove flare nuts attached to indoor and outdoor units,
then put them on pipe having completed burr removal.
(Not possible to put them on after flaring 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 selected.
5) Check
• Compare the flared work with Fig. 6.
• If flare is noted to be defective, cut off the flared section
and do flaring work again.
Pipe diameter B
[inch (mm)] [inch (mm)]
1/4 (ø6.35) 21/32 (17)
3/8 (ø9.52) 7/8 (22)
1/2 (ø12.7) 1-1/32 (26)
5/8 (ø15.88) 1-5/32 (29)
3-3. PIPE CONNECTION
• The connected pipe size differs depending the models and the capacities of indoor units.
Indoor unit capacity
Indoor unit: M series
Indoor unit: S series
Indoor unit: P series *1
*1 Refer to the installation manual of P series for details of MVZ-A and SVZ-KP.
• Use tightening torque table above as a guideline for indoor unit side union
joint section, and tighten using two wrenches. Excessive tightening damages
the flare section.
1) Do not apply refrigeration oil on screw threads. Excessive tightening torque
will result in damage on the screw.
2) For connection, first align the center, then tighten the first 3 to 4 turns of flare
nut by hand.
3) Tighten the flare nut with a torque wrench as specified in the table.
• Over-tightening may cause damage to the flare nut, resulting in refrigerant
leakage.
• Be sure to wrap insulation around the piping. Direct contact with the bare
piping may result in burns or frostbite.
3-4. INSULATION AND TAPING
1) Cover piping joints with pipe cover.
2) For outdoor unit side, surely insulate every piping including valves.
3) Using piping tape (E), apply taping starting from the entry of outdoor unit.
• Stop the end of piping tape (E) with tape (with adhesive agent attached).
• When piping have to be arranged through above ceiling, closet or where
the temperature and humidity are high, wind additional commercially sold
insulation to prevent condensation.
5
0.8 0.8 1.0 1.0 1.0
Clutch type tool for R410A Clutch type tool for R22
0 to 0.02
(0 to 0.5)
06 ~ 09 12
Liquid pipe size ø6.35 ø6.35
Gas pipe size ø9.52 ø9.52
Liquid pipe size ø6.35 ø6.35
Gas pipe size ø9.52 ø9.52
Liquid pipe size ø6.35 ø6.35
Gas pipe size ø9.52 ø12.7
WARNING
1.0 1.0
Good
Copper
pipe
Fig. 1
Flaring tool
Die
Flare nut
Wing nut type
Clutch type
Fig. 4
A [inch (mm)]
Wing nut type tool for R22
0.06 to 0.08
(1.5 to 2.0)
0.04 to 0.06
(1.0 to 1.5)
0.08 to 1.0
(2.0 to 2.5)
15
ø6.35
ø12.7
ø6.35
ø12.7
ø6.35
ø12.7
Indoor unit connection
Internal thread side
Tighten the flare nut
with a torque wrench.
Outdoor unit connection
No good
Copper pipe
Burr
Tilted Uneven Burred
Fig. 2
Smooth all
around
Copper pipe
B
Fig. 5
Tightening torque
ft-Ib N•m
10 to 13 13.7 to 17.7
25 to 30 34.4 to 41.2
36 to 42 49.1 to 56.9
54 to 58 73.5 to 78.5
WARNING
When installing the unit, securely
connect the refrigerant pipes before
starting the compressor.
CAUTION
When there are the ports which are
not used, make sure their nuts are
tightened securely.
Flare nut Union joint
External thread side
Grip the nut on the
union joint with a spanner.
Tighten the flare nut
with a torque wrench.
Spare reamer
Pipe cutter
Fig. 3
Inside is shin-
ing without any
scratches.
Even length
all around
Fig. 6
kgf•cm
140 to 180
350 to 420
500 to 580
750 to 800