Installing The Refrigerant Piping - Mitsubishi Electric PLA-A12BA4 Installation Manual

4. Installing the refrigerant piping

45 2
Flare cutting dimensions
Copper pipe O.D. Flare dimensions
(mm, inch) A dimensions (mm, inch)
6.35, 1/4 8.7 - 9.1, 11/32 - 23/64
9.52, 3/8 12.8 - 13.2, 1/2 - 33/64
12.7, 1/2 16.2 - 16.6, 41/64 - 21/32
15.88, 5/8 19.3 - 19.7, 49/64 - 25/32
19.05, 3/4 23.6 - 24.0, 15/16 - 61/64
B (mm, inch)
Copper pipe O.D.
Flare tool for R410A
mm (inch)
1.0 - 1.5, 3/64 - 1/16
6.35 (1/4")
9.52 (3/8") 1.0 - 1.5, 3/64 - 1/16
12.7 (1/2") 1.0 - 1.5, 3/64 - 1/16
15.88 (5/8") 1.0 - 1.5, 3/64 - 1/16
1.0 - 1.5, 3/64 - 1/16
19.05 (3/4")
Fig. 4-1
B
Die
Copper pipe
Fig. 4-2
Clutch type
4.1. Precautions
For devices that use R410A refrigerant
• Use ester oil, ether oil or alkylbenzene oil (small amount) as the
refrigeration oil applied to the fl ared sections.
• Use C1220 copper phosphorus for copper and copper alloy seamless pipes,
to connect the refrigerant pipes. Use refrigerant pipes with the thicknesses
specifi ed 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:
When installing or relocating, or servicing the air conditioner, use only the
specifi ed refrigerant (R410A) 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 specifi ed 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.
A12, A18
ø6.35 mm, ø1/4 inch
Liquid pipe
thickness 0.8mm, 1/32 inch
ø12.7 mm, ø1/2 inch
Gas pipe
thickness 0.8mm, 1/32 inch
• Do not use pipes thinner than those specifi ed above.
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, 212 °F
or more, thickness of 12 mm, 1/2 inch or more).
• The indoor parts of the drain pipe should be wrapped with polyethylene foam
insulation materials (specifi c gravity of 0.03, thickness of 9 mm, 23/64 inch or
more).
• Apply thin layer of refrigerant oil to pipe and joint seating surface before
tightening fl are nut.
• Use two wrenches to tighten piping connections.
• Use refrigerant piping insulation provided to insulate indoor unit connections.
Insulate carefully.
B Flare nut tightening torque
Copper pipe O.D. Flare nut O.D.
(mm, inch)
ø6.35, 1/4
ø6.35, 1/4
ø9.52, 3/8
ø12.7, 1/2
ø12.7, 1/2
ø15.88, 5/8
ø15.88, 5/8 36, 1-27/64
ø19.05, 3/4 36, 1-27/64
C Apply refrigerating machine oil over the entire fl are seat surface.
D Use correct fl are nuts meeting the pipe size of the outdoor unit.
Available pipe size
A12, A18
Liquid side ø6.35
Gas side ø12.7
: Factory fl are nut attachment to the heat exchanger.
A24, A30, A36, A42
ø9.52 mm, ø3/8 inch
thickness 0.8mm, 1/32 inch
ø15.88 mm, ø5/8 inch
thickness 1.0mm, 3/64 inch
Tightening torque
(mm, inch) (N-m, ftlbs)
17, 43/64 14-18, 10-13
22, 7/8 34-42, 25-30
22, 7/8 34-42, 25-30
26, 1-3/64 49-61, 35-44
29, 1-9/64 68-82, 49-59
29, 1-9/64 68-82, 49-59
100-120, 71-86
100-120, 71-86
A24, A30, A36, A42
ø9.52
ø15.88
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