5MXS48TVJU Installation Manual

9 English
Outdoor Unit Installation
4. Refrigerant piping
• Usethearenutxedtothemainunit.(Thisistopreventthearenutfromcrackingasaresultofdeteriorationovertime.)
• Topreventgasleakage,applyrefrigerationoilonlytotheinnersurfaceoftheare.(UserefrigerationoilforR410A.)
• Useatorquewrenchwhentighteningthearenutstopreventdamagetothearenutsandgasleakage.
• Alignthecentersofbotharesandtightenthearenuts3or4turnsbyhand,thentightenthemfullywithaspanneranda
torque wrench.
Do not apply refrigeration
oil to the outer surface.
Flare nut
Apply refrigeration
oil only to the inner
surface of the flare.
Do not apply refrigeration oil to
the flare nut to avoid tightening
with excessive torque.
Apply oil
Torque wrench
Piping union
Flare nut
Flare nut tightening torquePiping size
O.D. φ3/8 inch (9.5mm)
O.D. φ1/2 inch (12.7mm)
O.D. φ5/8 inch (15.9mm)
O.D. φ1/4 inch (6.4mm)
24-1/8 – 29-1/2ft • Ibf (32.7-39.9N • m)
36-1/2 – 44-1/2ft • lbf (49.5-60.3N • m)
45-5/8 – 55-5/8ft • lbf (61.8-75.4N • m)
10-1/2 – 12-3/4ft • lbf (14.2-17.2N • m)
Gas pipe
Liquid pipe
Width across flats
Valve cap tightening torque
Service port cap tightening torque
8 10-7/8ft • lbf
(10.7-14.7N • m)
3/4 inch (19mm)
12-5/8–15-3/8ft • lbf
(17.0-21.0N • m)
7/8 inch (22mm)
16-1/4– 19-7/8ft • lbf
(22.0-27.0N • m)
Cautions on pipe handling
• Protect the open end of the pipe from dust and moisture.
• All pipe bends should be as gentle as possible. Use a pipe bender for
If no flare cap is
available, cover
the flare mouth
with tape to keep
dirt and water out.
Be sure to
place a cap.
Selection of copper and heat insulation materials
• Insulation material: Polyethylene foam
• Heat transfer rate: 0.041 to 0.052W/mK (0.024 to 0.030Btu/fth°F
(0.035 to 0.045kcal/mh°C))
Be sure to use insulation that is designed for use with HVAC Systems.
• Be sure to insulate both the gas and liquid piping and observe the insulation
dimensions as below.
Gas pipe
Liquid pipe
Gas pipe
Liquid pipe
Finishing tape
Drain hose
Gas side
Piping size
O.D. 3/8 inch
O.D. 1/2 inch
O.D. 5/8 inch
O.D. 1/4 inch
1-3/16 inch (30mm)
or more
1-9/16 inch (40mm)
or more
1-15/16 inch (50mm)
or more
1-3/16 inch (30mm)
or more
0.031 inch (0.8mm)
0.039 inch (1.0mm)
0.031 inch (0.8mm)
I.D. 15/32-19/32 inch
I.D. 9/16-5/8 inch
I.D. 5/8-13/16 inch
I.D. 5/16-13/32 inch
13/32 inch
(10mm) Min.
Minimum bend radius
Piping thickness
Thermal insulation size
Thermal insulation
Liquid side
• Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
01_EN_3P537039-1.indd 9 9/12/2018 7:37:44 PM