6 Installation
Installer reference guide
14
35R5V1B RXM20~35R5V1B
R32 Split Series
4P519439-8H – 2020.07
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.
6.4.3
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
6.4.4
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).
6.4.5
To flare the pipe end
CAUTION
▪ Incomplete flaring may cause refrigerant gas leakage.
▪ Do NOT re-use flares. Use new flares to prevent
refrigerant gas leakage.
▪ Use flare nuts that are included with the unit. Using
different flare nuts may cause refrigerant gas leakage.
1
Cut the pipe end with a pipe cutter.
2
Remove burrs with the cut surface facing down so that the
chips do NOT enter the pipe.
a
b
a
Cut exactly at right angles.
b
Remove burrs.
3
Remove the flare nut from the stop valve and put the flare nut
on the pipe.
4
Flare the pipe. Set exactly at the position as shown in the
following figure.
A
Flare tool for R32
(clutch type)
Conventional flare tool
Clutch type
(Ridgid-type)
Wing nut type
(Imperial-type)
A
0~0.5 mm
1.0~1.5 mm
1.5~2.0 mm
5
Check that the flaring is properly made.
a
b
c
a
Flare’s inner surface MUST be flawless.
b
The pipe end MUST be evenly flared in a perfect circle.
c
Make sure the flare nut is fitted.
6.4.6
Using the stop valve and service port
CAUTION
Do NOT open the valves before flaring is complete. This
would cause refrigerant gas leakage.
To handle the stop valve
Take the following guidelines into account:
▪ The stop valves are factory closed.
▪ The following figure shows the stop valve parts required when
handling the valve.
c
d
a
b
a
Service port and service port cap
b
Valve stem
c
Field piping connection
d
Stem cap
▪ Keep both stop valves open during operation.
▪ Do NOT apply excessive force to the valve stem. Doing so may
break the valve body.
▪ ALWAYS make sure to secure the stop valve with a spanner, then
loosen or tighten the flare nut with a torque wrench. Do NOT place
the spanner on the stem cap, as this could cause a refrigerant
leak.
a
b
a
Spanner
b
Torque wrench
