Flaring Work And Pipe Connection - Mitsubishi Electric MXZ-6F122VF Manual De Instalación

3. FLARING WORK AND PIPE CONNECTION

3-1. PRECAUTIONS FOR DEVICES THAT USE R32 REFRIGERANT
• Use ester oil, ether oil, alkylbenzene oil (small amount) as the refrigeration oil applied to the flared sections.
• Use 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.
WARNING:
When installing or relocating, or servicing the air conditioner, use only the specified refrigerant (R32) to charge the refrigerant lines. Do not mix it with any
other refrigerant and do not allow air to remain in the lines.
If air is mixed with the refrigerant, then it can be the cause of abnormal high pressure in the refrigerant line, and may result in an explosion and other
hazards.
The use of any refrigerant other than that specified for the system will cause mechanical failure or 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
• Do not use pipes thinner than those specified above.
en
• Use 1/2 H or H pipes if the diameter is 19.05 mm or larger.
• Be 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
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 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.
Clutch
Pipe diameter Nut
type tool
(mm) (mm)
for R32,
R410A
ø6.35 (1/4") 17
ø9.52 (3/8") 22
0 to 0.5 1.0 to 1.5
ø12.7 (1/2") 26
ø15.88 (5/8") 29
3-3. PIPE CONNECTION
• The connected pipe size differs depending the models and the capacities of
indoor units.
Indoor unit capacity
Liquid pipe size
Indoor unit:
M series
Gas pipe size
Liquid pipe size
Indoor unit:
S series
Gas pipe size
Liquid pipe size
Indoor unit:
P series
Gas pipe size
*1 Use a joint pipe if the connection of the indoor unit differs.
• 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) Apply a thin coat of refrigeration oil (G) to the flared ends of the pipes and the
pipe connections of the outdoor unit. Do not apply refrigeration oil on screw
threads. Excessive tightening torque will result in damage on the screw.
2) Align the center of the pipe with that of the pipe connections of the outdoor
unit, then hand tighten the flare nut 3 to 4 turns.
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.
8
0.8 0.8 1.0 1.0 1.0
A (mm) Tightening torque
Clutch Wing nut
type tool type tool N•m
for R22 for R22
13.7 to 17.7 140 to 180
1.5 to
2.0
34.3 to 41.2 350 to 420
49.0 to 56.4 500 to 575
2.0 to
2.5
73.5 to 78.4 750 to 800
15 ~ 25 35 ~ 42 50 60
ø6.35 ø6.35 ø6.35 ø6.35
ø9.52 ø9.52 ø9.52 *1 ø12.7
ø6.35 ø6.35 ø6.35 ø6.35
ø9.52 ø9.52 ø12.7 ø15.88
- ø6.35 ø6.35 ø9.52
- ø12.7 ø12.7 ø15.88
1.0 1.0
Copper pipe
Burr
Spare reamer
kgf•cm
Die
Flare nut
71
ø6.35
ø12.7
ø9.52
ø15.88
ø9.52
ø15.88
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.
Good
Copper
pipe
Tilted Uneven Burred
Fig. 1
Flaring tool
Pipe cutter
Clutch type
Fig. 3
Smooth all
around
Copper pipe
Fig. 5
No good
Fig. 2
Wing nut type
Fig. 4
Inside is shin-
ing without any
scratches.
Even length
all around
Fig. 6