10
A
90
°
6. INDOOR/OUTDOOR UNIT CONNECTION FINISHING AND TEST RUN
6-1
Tools dedicated for the air conditioner with R410A refrigerant
The following tools are required for R410A refrigerant. Some R22 tools can be substituted for R410A tools.
The diameter of the service port on the stop valve in outdoor unit has been changed to prevent any other
refrigerant being charged into the unit. (Cap size has been changed from 7/16 UNF with 20 threads to 1/2 UNF
with 20 threads.)
R410A tools
Can R22 tools be used?
Description
R410A has high pressures beyond the measurement range of existing
gauges.
Gauge manifold
No
Port diameters have been changed to prevent any other refrigerant from
being charged into the unit.
Charge hose
No
Hose material and cap size have been changed to improve the pressure
resistance.
Gas leak detector
No
Dedicated for HFC refrigerant.
Torque wrench
Yes
1/4
No
1/2, 5/8
Flare tool
Yes
Clamp bar hole has been enlarged to reinforce the spring strength in the
tool.
Flare gauge
New
Provided for flaring work (to be used with R22 flare tool).
Vacuum pump adaptor
New
Provided to prevent the back flow of oil. This adapter enables you to use
existing vacuum pumps.
New
It is difficult to measure R410A with a charging cylinder because the refrig-
erant bubbles due to high pressure and high-speed vaporization.
No: Not substitutable for R410A Yes: Substitutable for R410A
Electronic scale for re-
frigerant charging
6-2
FLARING WORK
• Main cause of gas leakage is defect in flaring work.
Carry out correct flaring work in the following procedure.
2. Burrs removal
• Completely remove all burrs from the cut cross section of
pipe.
• Put the end of the copper pipe to downward direction as
you remove burrs in order to avoid to let burrs drop in the
piping.
Copper pipe
Good
No good
Tilted
Uneven
Burred
3. Putting nut on
• Remove flare nuts attached to indoor and outdoor units,
then put them on pipe having completed burr removal.
(not possible to put them on after flaring work)
• Flare nut for R410A pipe differs from R22 pipe. Refer to the
following table for detail.
Burr
Copper pipe
Spare
reamer
Pipe
cutter
4. Flaring work
• Carry out flaring work using flaring tool as shown below.
Flare nut
Copper pipe
1. Pipe cutting
• Cut the copper pipe correctly with pipe cutter.
• Firmly hold copper pipe in a die in the dimension shown in
the table above.
5. Check
• Compare the flared work with figure below.
• If flare is noted to be defective, cut off the flared section
and do flaring work again.
Die
Copper pipe
Flare nut
Die
Copper pipe
York
Flaring tool
Wing nut type
Clutch type
A (mm)
Outside
Conventional flare tool
diameter
Clutch type
Wing nut type
ø6.35 mm
0 to 0.5
1.0 to 1.5
1.5 to 2.0
ø12.7 mm
0 to 0.5
1.0 to 1.5
2.0 to 2.5
ø15.88 mm
0 to 0.5
1.0 to 1.5
2.0 to 2.5
Flare tool for
R410A clutch type
Smooth all around
Even length
all around
Inside is shining
without any scratches.
mm
inch
R410A
R22
ø6.35
1/4
17
17
ø12.7
1/2
26
24
ø15.88
5/8
29
27
