Flare Connection (Pipe Connection) - Fujitsu AOYG45LETL Installation Manual

5.3. Flare connection (pipe connection)

Do not use mineral oil on a flared part. Prevent mineral oil from getting into the system
as this would reduce the lifetime of the units.
While welding the pipes, be sure to blow dry nitrogen gas through them.
The maximum lengths of this product are shown in the table. If the units are further
apart than this, correct operation cannot be guaranteed.
5.3.1. Flaring
• Use special pipe cutter and flare tool exclusive for R410A.
(1) Cut the connection pipe to the necessary length with a pipe cutter.
(2) Hold the pipe downward so that the cuttings will not enter the pipe and remove any
burrs.
(3) Insert the flare nut (always use the flare nut attached to the indoor and outdoor
units respectively) onto the pipe and perform the flare processing with a flare tool.
Leakage of refrigerant may result if other flare nuts are used.
(4) Protect the pipes by pinching them or with tape to prevent dust, dirt, or water from
entering the pipes.
Check if [L] is flared uniformly
and is not cracked or scratched.
Pipe outside diameter
[mm (in.)]
6.35 (1/4)
9.52 (3/8)
12.70 (1/2)
15.88 (5/8)
19.05 (3/4)
Pipe outside diameter
[mm (in.)]
6.35 (1/4)
9.52 (3/8)
12.70 (1/2)
15.88 (5/8)
19.05 (3/4)
• When using conventional flare tools to flare R410A pipes, the dimension A should
be approximately 0.5 mm more than indicated in the table (for flaring with R410A
flare tools) to achieve the specified flaring. Use a thickness gauge to measure the
dimension A.
Width across flats Pipe outside
diameter [mm (in.)]
12.70 (1/2)
15.88 (5/8)
19.05 (3/4)
5.3.2. Bending pipes
To prevent breaking of the pipe, avoid sharp bends. Bend the pipe with a radius of
curvature of 100 mm to 150 mm.
If the pipe is bent repeatedly at the same place, it will break.
• If pipes are shaped by hand, be careful not to collapse them.
• Do not bend the pipes at an angle of more than 90°.
• When pipes are repeatedly bent or stretched, the material will harden, making it
difficult to bend or stretch them any more.
• Do not bend or stretch the pipes more than three times.
5.3.3. Pipe connection
Be sure to install the pipe against the port on the indoor unit and the outdoor 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 from the outdoor unit pipe until immediately before
connecting the connection pipe.
After installing the piping, make sure that the connection pipes do not touch the
compressor or outer panel. If the pipes touch the compressor or outer panel, they will
vibrate and produce noise.
CAUTION
B
Die
A
Pipe
Dimension A [mm]
Flare tool for R410A, clutch type
0 to 0.5
0
Dimension B [mm]
- 0.4
9.1
13.2
16.6
19.7
24.0
Width across flats
of Flare nut [mm]
6.35 (1/4) 17
9.52 (3/8) 22
26
29
36
CAUTION
CAUTION
(1) Detach the caps and plugs from the pipes.
(2) Center the pipe against the port on the outdoor unit, and then turn the flare nut by
hand.
(3) Tighten the flare nut of the connection pipe at the outdoor unit valve connector.
3-way valve (Liquid)
Flare nut
Connection pipe
(Liquid)
(4) After tightening the flare nut by hand, use a torque wrench to fully tighten it.
Hold the torque wrench at its grip, keeping it in a right angle with the pipe, in order to
tighten the flare nut correctly.
• Outer panel may be distorted if fastened only with a wrench. Be sure to fix the
elementary part with a spanner and fasten with a wrench (refer to below diagram).
• Do not apply force to the blank cap of the valve or hang a wrench, etc., on the cap. It may
cause leakage of refrigerant.
Blank cap
Holding
wrench
Flare nut [mm (in.)] Tightening torque [N·m (kgf·cm)]
6.35 (1/4) dia.
9.52 (3/8) dia.
12.70 (1/2) dia.
15.88 (5/8) dia.
19.05 (3/4) dia.
5.3.4. Handling precautions for the valves
• Mounted part of Blank cap is sealed for protection.
• Fasten blank cap tightly after opening valves.
Blank cap [mm (in.)] Tightening torque [N·m (kgf·cm)]
6.35 (1/4)
9.52 (3/8)
12.70 (1/2)
15.88 (5/8)
19.05 (3/4)
Operating the valves
• Use a hexagon wrench (size 4 mm).
• Opening (1) Insert the hexagon wrench into the valve shaft, and turn it
counterclockwise.
(2) Stop turning when the valve shaft can no longer be turned.
(Open position)
• Closing (1) Insert the hexagon wrench into the valve shaft, and turn it clockwise.
(2) Stop turning when the valve shaft can no longer be turned.
(Closed position)
Opening direction
Opening direction
Liquid pipe
3-way valve (Gas)
Flare nut
Connection pipe
(Gas)
CAUTION
Flare nut
Torque wrench
90°
Torque wrench
16 to 18 (160 to 180)
32 to 42 (320 to 420)
49 to 61 (490 to 610)
63 to 75 (630 to 750)
90 to 110 (900 to 1100)
Table A
20 to 25 (200 to 250)
20 to 25 (200 to 250)
28 to 32 (280 to 320)
30 to 35 (300 to 350)
35 to 40 (350 to 400)
Hexagon wrench
Seal (blank cap
installation portion)
Gas pipe
En-6