Refrigerant Pipe Work; Precautions; Connecting Pipes - Mitsubishi Electric EHST20-Serie Installationshandbuch

4
installation

4.5 refrigerant Pipe work

(Split Model Systems only)
Installation of refrigerant pipe work MUSt only be done by a technician with rele-
vant qualifications. Installation requirements may differ depending on the outdoor
unit selected. Please also refer to outdoor unit installation manual when connect-
ing refrigerant pipe work.
Gas side pipe size (mm) liquid side Pipe size (mm)
ø5.88 ø9.52

Precautions

For devices that use R40A refrigerant
• Use ester oil, ether oil or alkylbenzene oil (small amount) as the refrigeration
oil applied to the flared sections.
• Use C220 copper phosphorus for copper and copper alloy seamless pipes, to
connect the refrigerant pipes. Use refrigerant pipes with the thicknesses speci-
fied 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 moving the air conditioner, use only the specified refrig-
erant (r410A) to charge the refrigerant lines. do not mix it with any other
refrigerant and do not allow air to remain in the lines. Air enclosed in the
lines can cause pressure peaks resulting in a rupture and other hazards.
rP35, 50
Liquid pipe ø6.35 thickness 0.8 mm
Gas pipe ø2.7 thickness 0.8 mm
• Do not use pipes thinner than those specified above.
Connecting pipes (Figure 4.5.1)
• 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).
• Apply thin layer of refrigerant oil to pipe and joint seating surface before tight-
ening flare nut.
• Use two wrenches to tighten piping connections.
• Use refrigerant piping insulation to insulate indoor unit connections.
Flare nut tightening torque
Copper pipe O.d. Flare nut O.d.
(mm)
ø6.35
ø6.35
ø9.52
ø2.7
ø2.7
ø5.88
ø5.88
Apply refrigerating machine oil over the entire flare seat surface.
Use correct flare nuts matching the pipe size of the outdoor unit.
7
rP60-140/HrP71-125
ø9.52 thickness 0.8 mm
ø5.88 thickness .0 mm
tightening torque
(mm) (n·m)
7 4 - 8
22 34 - 42
22 34 - 42
26 49 - 6
29 68 - 82
29 68 - 82
36 00 - 20
45 2
Flare cutting dimensions
Flare nut tightening torque
<Figure 4.5.>
Flare cutting dimensions
Copper pipe O.d.
(mm)
ø 6.35
ø9.52
ø2.7
ø5.88
Die
Copper pipe
<Figure 4.5.2>
Copper pipe O.d.
(mm)
ø6.35 (1/4")
ø9.52 (3/8")
ø12.7 (1/2")
ø15.88 (5/8")
A
<Cylinder unit side>
<Figure 4.5.3>
Match the outer diameter of the refrigerant pipe between the outdoor unit and cyl-
inder unit with that of the refrigerant pipe on the outdoor unit.
If they do not match, connect the following adapter to the refrigerant pipe on the
cylinder unit.
Connected pipes
Model name
diameter (mm)
ø15.88 → ø12.7
PAC-SH50RJ-E
ø9.52 → ø6.35
PAC-SH30RJ-E
Flare dimensions
øA dimensions (mm)
8.7 - 9.
2.8 - 3.2
6.2 - 6.6
9.3 - 9.7
B
B (mm)
Flare tool for r410A
Clutch type
.0 - .5
.0 - .5
.0 - .5
.0 - .5
B
<Extension pipe side>
diameter A diameter B
(mm) (mm)
ø15.88 (5/8 F) ø12.7 (1/2 F)
ø 9.52 (3/8 F) ø 6.35 (1/4 F)