6
REFRIGERANT PIPING
Tightening connection
Align the centers of the connecting pipes and tighten
the flare nut as far as possible with your fingers. Then
tighten the nut with a spanner and torque wrench as
shown in the figure.
CAUTION
• Do not apply excess torque. Otherwise, the nut
may crack depending on the conditions.
Outer diam. of copper pipe
6.35 mm (diam.)
9.52 mm (diam.)
12.7 mm (diam.)
15.9 mm (diam.)
• Tightening torque of flare pipe connections
Pressure of R410A becomes higher than that of R22.
(Approx. 1.6 times) Therefore, using a torque wrench,
tighten firmly the flare pipe connecting sections which
connect the indoor and outdoor units up to the
specified tightening torque.
Incorrect connections may cause not only a gas
leakage, but also a trouble of the refrigeration cycle or
compressor damage.
Half union
Externally
threaded side
Use a wrench to secure.
(Unit : N•m)
Tightening torque
14 to 18 (1.4 to 1.8 kgf•m)
33 to 42 (3.3 to 4.2 kgf•m)
50 to 62 (5.0 to 6.2 kgf•m)
63 to 77 (6.3 to 7.7 kgf•m)
Flare at
indoor unit side
Flare at
outdoor unit side
Flare nut
Internally
threaded side
Use a torque wrench to tighten.
Pipe Shield for Flare Nut Connection
Joints in liquid and gas pipes of the indoor unit should
be insulated with an attached Pipe shield (13).
How to install the pipe shield
1. Cut the Pipe shield (13) to appropriate length.
2. Set the Pipe shield (13).
3. In case of a ceiling installation, orient the slit at the
top of the pipe.
4. Fix the Pipe shield (13) with vinyl tape.
Vinyl tape
12
Slit
(13) Pipe shield