Refrigerant Pipe And Drain Pipe - Mitsubishi Electric CITY MULTI PLFY-P NFMU-E Serie Manual De Instalación

3. Refrigerant pipe and drain pipe

F
Fig. 3-1
45° ±2°
Fig. 3-2
Refrigerant pipe sizes & Flare nut tightening torque
B
Liquid pipe
Pipe size
(mm, inch)
P05/08/12/15/18 ODø6.35, 1/4
A
Fig. 3-3
E 1/4 7-23/32 7-23/32
D
B
C
R410A
Gas pipe
Tightening torque Pipe size
(N∙m, ft∙lbs) (mm, inch)
14 to 18, 10 to 13 ODø12.7, 1/2
B
F
C
D
F
E
Refrigerant pipe and insulating material
A
(Procure locally)
Pipe cover (large) (Accessory)
B
Pipe cover (small) (Accessory)
C
Refrigerant pipe (gas)
D
Refrigerant pipe (liquid)
E
Band (Accessory)
F
Cross-sectional view of connection
G
Refrigerant pipe
H
Insulating material
I
Squeeze
J
3.1. Refrigerant and drainage piping locations of indoor
(inch)
unit (Fig. 3-1)
A
Drain pipe
A
Ceiling
B
Grille
C
Refrigerant pipe (liquid)
D
Refrigerant pipe (gas)
E
Main unit
F
3.2. Connecting pipes (Fig. 3-2)
• 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 (15/32 inch) or more).
• The indoor parts of the drain pipe should be wrapped with polyethylene foam insula-
tion materials (specific gravity of 0.03, thickness of 9 mm (11/32 inch) 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.
Warning:
When installing the unit, securely connect the refrigerant pipes before start-
ing the compressor.
Flare cutting dimensions
A
Copper pipe O.D.
(mm, inch)
ø6.35, 1/4
ø12.7, 1/2
Flare nut O.D.
Tightening torque Liquid pipe
(N∙m, ft∙lbs) (mm, inch)
49 to 61, 36 to 45 17, 21/32
Apply refrigerating machine oil over the entire flare seat surface.
C
3.3. Indoor unit (Fig. 3-3)
Heat insulation for refrigerant pipes:
Wrap the enclosed large-sized pipe cover around the gas pipe, making sure that
1
the end of the pipe cover touches the side of the unit.
Wrap the enclosed small-sized pipe cover around the liquid pipe, making sure
2
that the end of the pipe cover touches the side of the unit.
Secure both ends of each pipe cover with the enclosed bands. (Attach the bands
3
20 mm (25/32 inch) from the ends of the pipe cover.)
Make sure that the slit in the pipe cover is facing upward when it is installed.
• 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.)
Flare dimensions
øA dimensions (mm, inch)
8.7 to 9.1, 11/32 to 23/64
16.2 to 16.6, 5/8 to 21/32
Gas pipe
(mm, inch)
26, 1-1/32
5