21
English
Ins
tallation Pr
oc
edur
e
5
Check that the flaring is correct, referring to the
illustrations below for examples of incorrect flaring.
3
2
1
Correct
Inclined
Damaged
Surface
Cracked
Uneven
Thickness
CAUTION
• Keep the piping length at a minimum to minimize the
additional refrigerant charge due to piping extension.
• When connecting the pipes, make sure that
surrounding objects do not interfere with or contact
them to prevent refrigerant leakage due to physical
damage.
• Make sure that the spaces where the refrigerant pipes
are installed comply with national gas regulations.
• Be sure to perform works such as additional
refrigerant charging and pipe welding under the
conditions of good ventilation.
• Be sure to perform welding and piping works for
mechanical connections under the conditions that the
refrigerant does not circulate.
• When reconnecting the pipes, make sure to perform
flared-jointing newly to prevent refrigerant leakage.
• When working on the refrigerant pipes and the
flexible refrigerant connectors, be careful that they
are not damaged physically by surrounding objects.
• For installation with handling the R-32 refrigerant,
use the special tools for the R32 refrigerant (manifold
gauge, vacuum pump, charging hose, etc.).
• During tests never pressurize the appliances with
a pressure higher than the maximum allowable
pressure(as indicated on the nameplate of the unit).
• Never directly touch any accidental leaking
refrigerant. This could result in severe wounds caused
by frostbite.
• Never install a dryer to this unit in order to guarantee
its lifetime.
• If the pipes require brazing ensure that OFN(Oxygen
Free Nitrogen) is flowing through the system.
• Nitrogen blowing pressure range is 0.02 to 0.05 MPa.
• If you need a pipe longer than specified in piping
codes and standards, you must add refrigerant to the
pipe. Otherwise, the indoor unit may freeze.
• While removing burrs, put the pipe face down to
make sure that the burrs do not get in to the pipe.
Step 7 Installing oil traps
Check the following list and install an oil trap.
• Based on cooling operation, install it on the gas side
pipe only.
• Install the oil trap only in between the outdoor unit
and the first branch joint and it should be installed at
every 10 m.
• Radius of curvature (R) on the oil trap are as follows;
Pipe
diameter
(D, mm)
12.70 15.88 19.05 22.23 25.40 28.60 31.75
Radius of
curvature
(R, mm)
25 and
over
32 and
over
38 and
over
41 and
over
51 and
over
57 and
over
60 and
over
• Height of the oil trap (H): 4R ≤ H ≤ 6R
• When the indoor unit is installed at a higher place
than the outdoor unit
H
R
Outdoor Unit
Indoor Unit
Oil trap (Install it at
every 10 m)
