Refrigerant Pipe And Drain Pipe - Mitsubishi Electric CITY MULTI PLFY-M-VEM Series Installation Manual

4. Refrigerant pipe and drain pipe
F
D
60 271 357
E
C
Fig. 4-1
ø6.35 thickness 0.8 mm
ø12.7 thickness 0.8 mm
• Do not use pipes thinner than those specified above.
A
45° ± 2°
Fig. 4-2
A Flare cutting dimensions
Copper pipe O.D. Flare dimensions øA dimensions
(mm)
ø6.35
ø9.52
ø12.7
ø15.88
B Refrigerant pipe sizes & Flare nut tightening torque
Pipe size (mm)
M20/25/32/40/50 ODø6.35 (1/4")
M63/80/100/125 ODø9.52 (3/8")
C Apply refrigerating machine oil over the entire flare seat surface.
* Do not apply refrigerating machine oil to the screw portions.
(This will make the flare nuts more apt to loosen.)
D Be certain to use the flare nuts that are attached to the main unit.
(Use of commercially-available products may result in cracking.)
A
B
Models A
20, 25, 32, 40, 50 76
63, 80, 100, 125 79.5
ø9.52 thickness 0.8 mm
ø15.88 thickness 1.0 mm
B
C
D
(mm)
8.7 - 9.1
12.8 - 13.2
16.2 - 16.6
19.3 - 19.7
R32/R410A
Liquid pipe
Tightening torque (N·m)
14 - 18
34 - 42
4.1. Refrigerant and drainage piping locations of
indoor unit (Fig. 4-1)
The figure marked with * in the drawing represent the dimensions of the main unit
excluding those of the optional multi function casement.
A Drain pipe
B Ceiling
C Grille
D Refrigerant pipe (liquid)
E Refrigerant pipe (gas)
(mm)
F Main unit
B *
When the optional multi-functional casement is installed, add 135 mm to the dimen-
76.5
sions marked on the figure.
79.5
4.2. Precautions
For devices that use R32/R410A refrigerant
• Use 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 following table. 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 (R32/R410A) to charge the refrigerant lines. Do not mix it
with any other refrigerant and do not allow air to remain in the lines.
I f air is mixed with the refrigerant, then it can be the cause of abnormal high pres-
sure 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.
4.3. Connecting pipes (Fig. 4-2)
• 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.
Warning:
• Be careful of flying flare nut! (Internally pressurized)
Remove the flare nut as follows:
1. Loosen the nut until you hear a hissing noise.
2. Do not remove the nut until the gas has been completely released (i.e.,
hissing noise stops).
3. Check that the gas has been completely released, and then remove the
nut.
• When installing the unit, securely connect the refrigerant pipes before starting
the compressor.
Gas pipe
Pipe size (mm) Tightening torque (N·m)
ODø12.7 (1/2") 49 - 61
ODø15.88 (5/8") 68 - 82
Flare nut O.D.
Liquid pipe (mm) Gas pipe (mm)
17 26
22 29
en
5