– 14 –
A
Flaring diameter size: A (Unit: mm)
CAUTION
• Do not scratch the inner surface of the flared part when
removing burrs.
• Flare processing under the condition of scratches on
the inner surface of flare processing part will cause
refrigerant gas leak.
• Check that the flared part is not scratched, deformed,
stepped, or flattened, and that there are no chips
adhered or other problems, after flare processing.
• Do not apply refrigerating machine oil to the flare
surface.
* In case of flaring with the conventional flare tool,
pull it out approx. 0.5 mm more than that for R22 to
adjust to the specified flare size. The copper pipe
gauge is useful for adjusting projection margin size.
• The sealed gas was sealed at the atmospheric
pressure so when the flare nut is removed, there
will no “whooshing” sound: This is normal and is not
indicative of trouble.
• Use two wrenches to connect the indoor unit pipe.
Work using double spanner
• Use the tightening torque levels as listed in the table
below.
Outer dia. of
connecting pipe (mm)
Tightening torque (N•m)
6.4 14 to 18 (1.4 to 1.8 kgf•m)
9.5 34 to 42 (3.4 to 4.2 kgf•m)
12.7 49 to 61 (4.9 to 6.1 kgf•m)
15.9 63 to 77 (6.3 to 7.7 kgf•m)
▼ Tightening torque of flare pipe connections.
Incorrect connections may cause not only a gas leak,
but also a trouble of the refrigeration cycle.
Align the centres 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
Tightening with an excessive torque may crack the nut
depending on installation conditions.
■
Evacuation
Perform vacuuming from the charge port of valve of
the outdoor unit by using a vacuum pump.
For details, follow to the Installation Manual attached to
the outdoor unit.
• Do not use the refrigerant sealed in the outdoor unit
for evacuation.
REQUIREMENT
For the tools such as charge hose, use those
manufactured exclusively for R32.
Refrigerant amount to be added
For addition of the refrigerant, add refrigerant “R32”
referring to the attached Installation Manual of outdoor
unit.
Use a scale to charge the refrigerant of specified
amount.
REQUIREMENT
• Charging an excessive or too little amount of
refrigerant causes a trouble of the compressor.
Charge the refrigerant of specified amount.
• A personnel who charged the refrigerant should
write down the pipe length and the added refrigerant
amount in the F-GAS label of the outdoor unit. It is
necessary to fix the compressor and refrigeration
cycle malfunction.
Outer dia. of copper pipe A
+0
–0.4
6.4 9.1
9.5 13.2
12.7 16.6
15.9 19.7
Attached
banding band
Fix it with vinyl tape
Face the incision upward.
Local piping side
Attached heat insulation
pipe
Open the valve fully
Open the valve of the outdoor unit fully. A 4 mm-
hexagonal wrench is required for opening the valve.
For details, refer to the Installation Manual attached
to the outdoor unit.
Gas leak check
Check with a leak detector or soap water whether gas
leaks or not, from the pipe connecting section or cap
of the valve.
REQUIREMENT
Use a leak detector manufactured exclusively for HFC
refrigerant (R32, R134a, R410A, etc.).
Heat insulation process
Apply heat insulation for the pipes separately at liquid
side and gas side.
• For the heat insulation to the pipes at gas side, use
the material with heat-resisting temperature 120 °C
or higher.
• To use the attached heat insulation pipe, apply the
heat insulation to the pipe connecting section of the
indoor unit securely without gap.
REQUIREMENT
• Apply the heat insulation to the pipe connecting
section of the indoor unit securely up to the root
without exposure of the pipe. (The pipe exposed to
the outside causes water leak.)
• Wrap heat insulator with its slits facing up (ceiling
side).
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