(1) When bending the pipe, be careful not to crush it.
(2) To prevent breaking of the pipe, avoid sharp bends.
Bend the pipe with a radius of curvature of 70 mm or over.
(3) If the copper pipe is bend the pipe or pulled to often, it will become stiff. Do not
bend the pipes more than three times at one place.
Flare nut tightening torque
Flare nut [mm (in.)]
6.35 (1/4) dia.
9.52 (3/8) dia.
12.70 (1/2) dia.
Pipe outside diameter
Pipe outside diameter [mm (in.)]
Fasten a ﬂ are nut with a torque wrench as instructed in this manual. If fastened too
tight, the ﬂ are nut may be broken after a long period of time and cause a leakage of
Install heat insulation around both the gas and liquid pipes. Failure to do so may cause
Use heat insulation with heat resistance above 248 °F. (Reverse cycle model only)
In addition, if the humidity level at the installation location of the refrigerant piping is
expected to exceed 70%, install heat insulation around the refrigerant piping. If the
expected humidity level is 70-80%, use heat insulation that is 15 mm or thicker and if
the expected humidity exceeds 80%, use heat insulation that is 20 mm or thicker.
If heat insulation is used that is not as thick as speciﬁ ed, condensation may form on the
surface of the insulation.
In addition, use heat insulation with heat conductivity of 0.045 W/(m·K) or less (at 68 °F).
(1) Remove the cap, and connect the gauge manifold and the vacuum pump to the
charging valve by the service hoses.
(2) Vacuum the indoor unit and the connecting pipes until the pressure gauge
indicates -0.1 MPa (-76 cmHg).
(3) When -0.1 MPa (-76 cmHg) is reached, operate the vacuum pump for at least
(4) Disconnect the service hoses and ﬁ t the cap to the charging valve to the speciﬁ ed
(5) Remove the blank caps, and fully open the spindles of the 2-way and 3-way
valves with a hexagon wrench [Torque: 2.9 N·m (30 kgf·cm)].
(6) Tighten the blank caps of the 2-way valve and 3-way valve to the speciﬁ ed torque.
Tightening torque [N
6.35 mm (1/4 in.)
9.52 mm (3/8 in.)
12.70 mm (1/2 in.)
Charging port cap
with valve core
To prevent gas leakage, coat the ﬂ are
surface with refrigerator oil.
Tightening torque [N
16 to 18 (11.8 to 13.3)
32 to 42 (23.6 to 31.0)
49 to 61 (36.1 to 45.0)
A [mm (in.)]
Flare tool for R410A, clutch type
0 to 0.5 (0 to 1/32)
20 to 25 (14.8 to 18.4)
28 to 32 (20.7 to 23.6)
10 to 12 (7.4 to 8.8)
Use a 4 mm
Do not purge the air with refrigerants, but use a vacuum pump to vacuum the
There is no extra refrigerant in the outdoor unit for air purging.
Use a vacuum pump and gauge manifold and charging hose for R410A exclusively.
Using the same vacuum for different refrigerants may damage the vacuum pump or the
When moving and installing the air conditioner, do not mix gas other than the
speciﬁ ed refrigerant R410A inside the refrigerant cycle.
When charging the refrigerant R410A, always use an electronic balance for refrig-
erant charging (to measure the refrigerant by weight).
When charging the refrigerant, take into account the
slight change in the composition of the gas and liquid
phases, and always charge from the liquid phase side
whose composition is stable.
Add refrigerant from the charging valve after the comple-
tion of the work.
If the units are further apart than the maximum pipe length, correct operation can-
not be guaranteed.
GAS LEAKAGE INSPECTION
After connecting the piping, check the all joints for gas leakage with gas leak detector.
When inspecting gas leakage, always use the vacuum pump for pressure. Do not use
5.7. TEST RUN
Perform test operation and check items below.
For the test operation method, refer to the operating manual.
The outdoor unit, may not operate, depending on the room temperature. In this
case, keep on pressing the MANUAL AUTO button of the indoor unit for more than
10 seconds. The operation indicator lamp and timer indicator lamp will begin to ﬂ ash
simultaneously during cooling test run. Then, heating test run will begin in about three
minutes when HEAT is selected by the remote control operation. (Please follow the
operating manual for remote control operation.)
To end test operation, keep on pressing the MANUAL AUTO button of the indoor unit for
more than 3 seconds.
(When the air conditioner is run by pressing the MANUAL AUTO button, the OPERA-
TION indicator lamp and TIMER indicator lamp of the indoor unit will simultaneously
ﬂ ash slowly.)
(1) Is there any abnormal noise and vibration during operation?
(2) Will noise, wind, or drain water from the unit disturb the neighbors?
(3) Is there any gas leakage?
Always turn on the power 12 hours prior to the start of the operation in order to
ensure compressor protection.
Use a clean gauge manifold
and charging hose for R410A