6.1.
Installation tools
Make sure to use installation tools (gauge manifold charge hose,
etc.) that are exclusively used for R410A installations to withstand the
pressure and to prevent foreign materials (e.g. mineral oils such as
SUNISO and moisture) from mixing into the system.
(The screw specifications differ for R410A and R407C.)
Use a 2-stage vacuum pump with a non-return valve which can
evacuate to –100.7 kPa (5 Torr, –755 mm Hg).
Make sure the pump oil does not flow oppositely into
NOTE
the system while the pump is not working.
6.2.
Selection of piping material
1.
Foreign materials inside pipes (including oils for fabrication)
must be 30 mg/10 m or less.
2.
Use the following material specification for refrigerant piping:
Size: determine the proper size referring to chapter
"6.6. Example of connection" on page 8.
Construction material: phosphoric acid deoxidized seamless
copper for refrigerant.
Temper grade: use piping with temper grade in function of the
pipe diameter as listed in the table below.
Pipe Ø
≤15.9
≥19.1
O = Annealed
1/2H = Half hard
The pipe thickness of the refrigerant piping should comply
with relevant local and national regulations. The minimal pipe
thickness for R410A piping must be in accordance with the
table below.
Minimal thickness
Pipe Ø
t (mm)
6.4
0.80
9.5
0.80
12.7
0.80
15.9
0.99
19.1
0.80
3.
Make sure to use the particular branches of piping that have
been selected referring to chapter "6.6. Example of connection"
on page 8.
4.
In case the required pipe sizes (inch sizes) are not available, it is
also allowed to use other diameters (mm sizes), taken the
following into account:
select the pipe size nearest to the required size.
use the suitable adapters for the change-over from inch to
mm pipes (field supply).
5.
Precautions when selecting branch piping
When the equivalent pipe length between outdoor and indoor
units is 90 m or more, the size of the main pipes (both gas side
and liquid side) must be increased.
Depending on the length of the piping, the capacity may drop,
but even in such a case it is possible to increase the size of the
main pipes. Refer to page 9. If the recommended pipe size is not
available, stick to the original pipe diameter (which may result in
a small capacity decrease).
Installation manual
5
Temper grade of piping material
O
1/2H
Minimal thickness
Pipe Ø
t (mm)
22.2
0.80
28.6
0.99
34.9
1.21
41.3
1.43
6.3.
Pipe connection
Be sure to perform a nitrogen blow when brazing and to read the
paragraph "Caution to be taken when brazing refrigerant piping" on
page 4 first.
NOTE
The pressure regulator for the nitrogen released when
doing the brazing should be set to 0.02 MPa or less.
(See figure 10)
1
Refrigerant piping
2
Location to be brazed
3
Nitrogen
4
Taping
5
Manual valve
6
Regulator
7
Nitrogen
Do not use anti-oxidants when brazing the pipe joints.
Residue can clog pipes and break equipment.
6.4.
Connecting the refrigerant piping
1
Front connection or side connection
Installation of refrigerant piping is possible as front connection or
side connection (when taken out from the bottom) as shown in
the figure.
1
2
1
Left-side connection
2
Front connection
3
Right-side connection
Precautions when knocking out knock holes
NOTE
Be sure to avoid damaging the casing
After knocking out the holes, we recommend you
remove the burrs and paint the edges and areas
around the edges using the repair paint to prevent
rusting.
When passing electrical wiring through the knock
holes, wrap the wiring with protective tape to
prevent damage.
3
U-5~18MX4XPQ
Urban Multi air conditioner
4PW28163-1C