York HIC4008B21S Installation And Maintenance Manual page 20

2. Use specific flare nut attached with the unit.
3. Verify that there are no scratches, burrs stuck to internal surfaces, or surface deformations at the flared opening.
4. Before tightening the flare nut, apply the (Field-Supplied) refrigerant oil in a thin layer over the flared
part. (Do not apply the oil on other areas.) Tighten the flare nut for the liquid pipe to the specified torque
with two spanners. Then, tighten the flare nut for the gas piping in the same way. After the tightening
work has been completed, check that no refrigerant leakage occurs.
NOTES:
1. Refrigerant oil is field-supplied.
[Ethereal Oil FVC50K, FVC68D (Idemitsu Kousan Co. Ltd.)]
2. If refrigerant comes into contact with decorative panel surfaces, damage in the form of cracks can
occur on panel surfaces. Use with caution.
Apply Refrigerant Oil.
Do not apply
the refrigerant
oil to the
outside of
the flared
opening.
5. Wherever buried piping exists on site, make sure there is a service doorway to provide adequate access
to inspect piping sockets and elbows, and for interconnecting parts.
6. Piping must be reinforced to withstand earthquakes so as not to be damaged by an external force.
7. Do not tightly secure refrigerant piping to accommodate expansion and contraction.
8. Prevent the pipes from contacting weak portions such as wall, ceiling, etc. (Otherwise, abnormal sound
may be heard due to vibration of the piping.)
9. Leak test all piping and connections. The procedures should be performed in accordance with the
"Installation and Maintenance Manual" for the outdoor unit.
10. If temperature and humidity inside the ceiling exceed 80.6°F (27°C)/RH80%, condensation occurs
on the surface of the accessory insulation. Wrap additional insulation (approximately 3/16~3/8 inch
(5~10mm) thickness) around the accessory insulation of the refrigerant pipe as a preventive measure.
11. Insulate each flare connection without gap with accessory insulations to prevent condensation. Then
insulate each refrigerant pipe as well.
● Do not apply excessive force to the flare nut when tightening. If applied, the flare nut may crack
due to stress fracture and refrigerant leakage may occur. Use the correct torque specifications.
● Make sure that a refrigerant leak test has been performed. Refrigerant (Fluorocarbon) for this unit is
non-flammable, non-toxic, and odorless. If the refrigerant should somehow escape and come into
contact with flame, toxic gas will form. This gas is heavier than air and will settle near floor areas
and spread where it can cause suffocation to those nearby.
16
Securely fasten cable bands and the vinyl tape
in order to prevent the accumulation of moisture.
Fasten with cable bands
at three locations along the pipe
(Accessory).
Unit
Side
Insulation Material
(Factory-Supplied)
Check for any clearance between
the indoor unit and the insulation.
Required Tightening Torque
Pipe Size
1/4 inch (6.35 mm)
3/8 inch (9.52 mm)
1/2 inch (12.7 mm)
5/8 inch (15.88 mm) 50.2 - 60.5 ft·lbs (68 - 82 N·m)
Secure the vinyl tape position at the vertical part
(Insulation for Refrigerant Pipe (Accessory)).
Refrigerant Pipe
(Field-Supplied)
Insulation for
Refrigerant Pipe
(Field-Supplied)
(JIS B 8607)
Tightening Torque
10.3 - 13.3 ft·lbs (14 - 18 N·m)
25.1 - 31.0 ft·lbs (34 - 42 N·m)
36.1 - 45.0 ft·lbs (49 - 61 N·m)
P5417054