72
S4179544
72
S4179544
Caution before Connecting Tubes Tightly
(1)
Apply a sealing cap or water-proof tape to
prevent dust or water from entering the tubes
before they are used.
(2)
Apply refrigerant lubricant to the matching
surfaces of the flare and union before connecting
them together. This helps to reduce gas leaks.
(Fig. 8-4)
(3)
For proper connection, align the union tube and
flare tube with each other, then screw in the flare
nut lightly at first to obtain a smooth match. (Fig.
8-5)
●
Adjust the shape of the narrow tube (liquid tube)
using a tube bender at the installation site and
connect it to the narrow tubing side (liquid tubing
side) valve using a flare.
8-2. Connecting Wide Tubing Side
Cautions During Brazing
●
Replace air inside the tube with nitrogen gas to
prevent copper oxide film from forming during
the brazing process.
●
Do not allow the tubing to get too hot during
brazing.
The nitrogen gas inside the tubing may over-
heat, causing refrigerant system valves to
become damaged. Therefore allow the tubing to
cool between brazing.
8-3. Connecting Tubing between Indoor and
Outdoor Units
(1)
Tightly connect the indoor-side refrigerant tubing
extended from the wall with the outdoor-side
tubing.
(2)
To fasten the flare nuts, apply specified torque as
follows:
Tube Diameter
6.35 mm (1/4”)
9.52 mm (3/8”)
12.7 mm (1/2”)
15.88 mm (5/8”)
19.05 mm (3/4”)
25.4 (1”) 28.58 (1-1/8”)
Bolt to fasten flange
Apply refrigerant
lubricant here and here
0129_M_I
Union
Flare nut
0130_M_I
Torque wrench
Spanner
Indoor unit
Outdoor unit
0131_C_I
Fig. 8-4
Fig. 8-5
Fig. 8-6
Tightening Torque, Approximate
140 — 180 kg-cm
(120 — 160 Ibs-in.)
340 — 420 kg-cm
(300 — 360 Ibs-in.)
490 — 610 kg-cm
(430 — 530 Ibs-in.)
680 — 820 kg-cm
(590 — 710 Ibs-in.)
1000 — 1200 kg-cm
(870 — 1040 Ibs-in.)
300 — 350 kg-cm
(260 — 310 Ibs-in.)
