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Technical Information
3.1.3 Connecting the Pipe at the Indoor Unit Side
Detach the caps and plugs from the pipes.
CAUTION!
Be sure to apply the pipe against the port on the indoor unit correctly. If the centering is improper, the flare nut cannot be
tightened smoothly. If the flare nut is forced to turn, the threads will be damaged.
Do not remove the flare nut until the connection pipe is to be connected so as to prevent dust and impurities from coming
into the pipe system.
When connecting the pipe to the unit or removing it from the unit, please do use both the spanner and the torque wrench
(Figure 3-3-4).
When connecting, smear both inside and outside of the flare nut with refrigeration oil, screw it hand tight and then tighten it
with the spanner.
Refer to Table 3-3-1 to check if the wrench has been tightened properly (too tight would mangle the nut and lead to leakage).
Examine the connection pipe to see if it leaks, then take the treatment of heat insulation, as shown in the Figure 3-3-4.
Use the medium-sized sponge to insulate the coupler of the gas pipe.
U-Match Series DC Inverter Service Manual
82
Sponge
Threaded fastener(×4)
Liquid pipe
Gas inlet pipe
Heat insulation sheath
(for the gas tube)
Heat insulation sheath
(for the liquid tube)
Figure 3-3-4
Table 3-3-1 Flare nut tightening torque
Pipe Diameter
Tightening Torque
6mm (1/4inch)
15~30N·m (11~22ft.-1b.)
9.5mm (3/8inch)
35~40N·m (26~29ft.-1b.)
12.7mm (1/2inch)
45~50N·m (33~37ft.-1b.)
16mm (5/8inch)
60~65N·m (44~48ft.-1b.)
Be sure to connect the gas pipe after connecting the liquid pipe completely.
3.1.4 Connecting the Pipe at the Outdoor Side Unit
Tighten the flare nut of the connection pipe at the outdoor unit valve connector. The tightening method
is the same as that as at the indoor side.
Gas pipe
Liquid pipe
Pipe
coupling
or
or
3-way valve
2-way valve
Figure 3-3-5
Table 3-3-1 Flare nut tightening torque
Pipe Diameter
Tightening Torque
6mm (1/4inch)
15~30N·m (11~22ft.-1b.)
9.5mm (3/8inch)
35~40N·m (26~29ft.-1b.)
12.7mm (1/2inch)
45~50N·m (33~37ft.-1b.)
16mm (5/8inch)
60~65N·m (44~48ft.-1b.)
Summary of Contents for AC Pro C Series
Page 90: ...Technical Information...