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Piping installation
Installer reference guide
38
3(A)MXM+3(A)MXF+4MXM+5MXM
R32 Split series
4P600463-1C – 2020.08
WARNING
Connect the refrigerant piping securely before running the compressor. If the
refrigerant piping is NOT connected and the stop valve is open when the compressor
is run, air will be sucked in. This will cause abnormal pressure in the refrigeration
cycle, which may result in equipment damage and even injury.
NOTICE
Even if the stop valve is fully closed, the refrigerant may slowly leak out. Do NOT
leave the flare nut removed for long period of time.
7.2.3 Guidelines when connecting the refrigerant piping
Take the following guidelines into account when connecting pipes:
▪
Coat the flare inner surface with ether oil or ester oil when connecting a flare
nut. Tighten 3 or 4 turns by hand, before tightening firmly.
▪
ALWAYS use 2 wrenches together when loosening a flare nut.
▪
ALWAYS use a spanner and torque wrench together to tighten the flare nut when
connecting the piping. This to prevent nut cracking and leaks.
a
b
c
d
a
Torque wrench
b
Spanner
c
Piping union
d
Flare nut
Piping size (mm)
Tightening torque
(N•m)
Flare dimensions
(A) (mm)
Flare shape (mm)
Ø6.4
15~17
8.7~9.1
R=
0.4~0.8
±2
45°
90°
±2
ØA
Ø9.5
33~39
12.8~13.2
Ø12.7
50~60
16.2~16.6
Ø15.9
62~75
19.3~19.7
7.2.4 Pipe bending guidelines
Use a pipe bender for bending. All pipe bends should be as gentle as possible
(bending radius should be 30~40 mm or larger).