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8
Refrigerant piping
Refrigerant piping
1. Use general copper pipes with a wall thickness
of 0.03" (0.8 mm) for Ø1/2" (12.7 mm), and with
a wall thickness of 0.04" (1.0 mm) for Ø7/8"
(22.2 mm) (half hard).
Do not use any copper pipes with a wall
thickness less than these thicknesses.
2. Flare nut and flare works are also different from
those of the conventional refrigerant.
Take out the flare nut attached to the main unit of
the air conditioner, and use it.
REQUIREMENT
When the refrigerant pipe is long, provide support
brackets at intervals of 8'2" to 9'10" (2.5 m to 3 m)
to clamp the refrigerant pipe. Otherwise, abnormal
sound may be generated.
CAUTION
Important 4 points for piping work
1. Remove dust and moisture from the inside of the
connecting pipes.
2. Tight connection (between pipes and unit)
3. Evacuate the air in the connecting pipes using
VACUUM PUMP.
4. Check the gas leakage. (Connected points)
Permissible piping length
and height difference
They vary according to the outdoor unit.
For details, refer to the Installation Manual attached to
the outdoor unit.
Pipe size
Model
Pipe size
Remarks
A(Gas)
Ø7/8" (22.2)
0721
0961
B(Liquid)
Ø1/2" (12.7)
Use the SOCKET
A(Gas)
Ø1.1/8" (28.6)
(Accessory)
1201
Use the LIQUID JOINT
B(Liquid)
Ø5/8" (15.9)
PIPE (Accessory)
31-EN
Liquid side refrigerant pipe
connection
Flaring
Cut the pipe with a pipe cutter.
Remove burrs completely.
Remaining burrs may cause gas leakage.
Insert a flare nut into the pipe, and flare the pipe.
As the flaring sizes of R410A differ from those of
refrigerant R22, the flare tools newly manufactured
for R410A are recommended.
However, the conventional
tools can be used by adjusting
projection margin of the copper
pipe.
Projection margin in fl aring: B (Unit: mm)
RIDGID (Clutch type)
Outside diameter
R410A tool
Conventional
size (mm)
used
tool used
1/4" (6.4), 3/8" (9.5)
0.04" (1.0) to
0 - 0.02" (0.5)
0.06" (1.5)
1/2" (12.7), 5/8" (15.9)
Flaring dia. meter size: A (Unit: mm)
Outside diameter
+0
A
-0.4
size (mm)
A
1/4" (6.4)
0.4" (9.1)
3/8" (9.5)
0.5" (13.2)
1/2" (12.7)
0.7" (16.6)
5/8" (15.9)
0.8" (19.7)
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.
Tightening connection
CAUTION
Do not apply excessive torque. Otherwise, the nut
may crack depending on the conditions.
Outside diameter size
Tightening torque
(mm)
1/4" (6.4 mm)
11 - 14 (14 - 18)
3/8" (9.5 mm)
25 - 31 (34 - 42)
1/2" (12.7 mm)
36 - 45 (49 - 61)
5/8" (15.9 mm)
47 - 57 (68 - 82)
Tightening torque of fl are pipe connections
B
Pressure of R410A is higher than that of R22.
(Approx. 1.6 times) Therefore, using a torque wrench,
tighten the fl are pipe connecting sections which
connect the indoor and outdoor units of the specifi ed
tightening torque.
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 fl are nut as far as possible with your fi ngers. Then
tighten the nut with a spanner and torque wrench as
shown in the fi gure.
Half union
Flare nut
Externally
threaded side
Use a wrench to secure.
Use a torque wrench to tighten.
REQUIREMENT
Tightening with an excessive torque may crack the
nut depending on installation conditions.
Tighten the nut within the specifi ed tightening
torque.
Gas side refrigerant pipe
connection
Turn up the pipe insulation to the unit side.
Wrap the pipe with wet cloth.
Turn up pipe
insulation
Wet cloth
Remove the all
brazed part.
Remove the cup on the gas side piping by using a
brazing machine.
– 16 –
CAUTION
Do not burn the pipe insulation.
Be careful for the flame, due to the brazing
process on the ceiling.
Connection pipe
Locally procured
Ø7/8" (22.2 mm)
Braze the connection piping to the joint part.
Braze all around
Turn back the pipe insulation and tie up with a
banding band.
Tie up with a banding
band.
Internally
threaded side
Airtight test / air purge, etc.
For air tightness test, adding refrigerant, refer to the
Installation Manual attached to the outdoor unit.
CAUTION
Do not supply power to the indoor unit until the
airtight test and vacuuming are completed. (If the
indoor unit is powered on, the pulse motor valve is
fully closed, which extends the time for vacuuming.)
Open the valve fully
Open the valve of the outdoor unit fully.
Remove the cap
EN
EN
ID
32-EN
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