80
S4359146
10-4. Precautions 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 the
brazing process.
The nitrogen gas inside the tubing may overheat,
causing refrigerant system valves to become
damaged. Therefore allow the tubing to cool be-
tween brazings.
Fig. 10-6
Fig. 10-7
Fig. 10-8
Torque wrench
Spanner
Indoor unit
Outdoor unit
0131_C_I
Never grasp the drain or refrigerant connecting
outlets when moving the unit.
Fig. 10-9
10-5. Connecting Tubing between Indoor and
Outdoor Units
(1) Tightly connect the indoor side refrigerant tubing
with the outdoor side tubing. (Fig. 10-6)
(2)
To fasten the flare nuts, apply specified torque as:
Table 10-1
Unit side
insulator
Insulation tape (white)
(supplied)
Seal (supplied)
Flare insulator (supplied)
Tube insulator
(not supplied)
Vinyl clamps (supplied)
Flare nut
1015_X_I
Insulation
Thickness:
Min. 5/16 in.
Wide tube
Narrow tube
Thickness:
Min. 5/16 in.
0999_C_I
Refrigerant tubing
Tightening Torque
Approx. 120 — 160 Ibs-in.
(140 — 180 kg-cm)
Approx. 300 — 360 lbs-in.
(340 — 420 kg-cm)
Approx. 870 — 1040 lbs-in.
(1000 — 1200 kg-cm)
Tube Dia.
1/4" (6.35 mm)
3/8" (9.52 mm)
3/4" (19.05 mm)
10-6. Insulating the Refrigerant Tubing
Always insulate tubes after
draining water and complet-
ing leak tests on all connec-
tion points.
To avoid condensation and water leaks, the wide tube
(gas line) must be insulated with the supplied insula-
tion materials.
Taping the flare nuts
Wind white insulation tape around the flare nuts at the
wide tube connections. Place the seal (supplied) on
the unit. Then cover up the tubing connections with the
flare nut insulator, and cover the gap at the union with
the supplied black insulation tape. Finally, fix the
insulator at both ends with vinyl clamps. (Fig. 10-8)
Insulation material
The material used for insulation must have good
insuIation characteristics, be easy to use, be age
resistant, and must not easily absorb moisture.
After a tube has been insu-
lated, never try to bend it
into a narrow curve because
it can cause the tube to
break or crack.
CAUTION
Important
CAUTION
Seal
Flare
insulator
Vinyl
clamp
Insulation
tape
Refrigerant tubing and insulator
(not supplied)
Drain pipe and insulator
(not supplied)
Drain insulator
and clamp.
Large
(supplied)
Packing
clamp.
Small
hose band
(supplied)
1373_X_I