Installing The Refrigerant Piping - Mitsubishi Electric Mr. SLIM Mr. SLIM S KA Series Installation Manual

4. Installing the refrigerant piping

A
45±2°
en
A Flare cutting dimensions
Copper pipe O.D.
(mm)
ø9.52
ø15.88
E
Copper pipe O.D.
(mm)
ø9.52 (3/8")
ø15.88 (5/8")
8
B
C
Fig. 4-1
Flare dimensions øA
dimensions (mm)
12.8 - 13.2
19.3 - 19.7
B
E Die
F Copper pipe
F
Fig. 4-2
B (mm)
Flare tool for R32/R410A
Clutch type
0 - 0.5
0 - 0.5
4.1. Precautions
For devices that use R32/R410A refrigerant
• Use the refrigerant oil (small amount) 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 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.
Warning:
W hen installing or relocating, or servicing the air conditioner, use only the
specified refrigerant written on outdoor unit 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.
ø9.52 thickness 0.8 mm
ø15.88 thickness 1.0 mm
• Do not use pipes thinner than those specified above.
D
4.2. 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 or
more, thickness of 12 mm 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 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.
Insulate carefully.
• After connecting the refrigerant piping to the indoor unit, be sure to test the pipe
connections for gas leakage with nitrogen gas. (Check that there is no refrigerant
leakage from the refrigerant piping to the indoor unit.)
• Use flared nut installed to this indoor unit.
• In case of reconnecting the refrigerant pipes after detaching, make the flared part
of pipe re-fabricated.
Flare nut tightening torque
B
Copper pipe O.D.
(mm)
ø9.52
ø15.88
Apply refrigerating machine oil over the entire flare seat surface.
C
Do not apply refrigerating machine oil to the screw portions.
(This will make the flare nuts more apt to loosen.)
Be certain to use the flare nuts that are attached to the main unit.
D
(Use of commercially-available products may result in cracking.)
Flare nut O.D. Tightening torque
(mm) (N·m)
22 34 - 42
29 68 - 82