Hitachi RPK-0.6FSNH3M Installations- Und Betriebshandbuch Seite 35

Refrigerant piping work
17.2 PIPING CONNECTION
C A U T I O N
Avoid attaching the refrigerant or the refrigerant oil to the upper
part of indoor unit. Otherwise, it will be damaged the indoor unit
cover and it may cause falling of indoor unit. If the refrigerant or
the refrigerant oil is attached, wipe it off completely.
1 Perform the flaring work as shown below.
2 Use specific flare nut.
3 Check that there are no scratch, swarf, deformation, gap, etc.
at the flaring part.
4 Apply the refrigerant oil in a thin layer to the inside of the fla-
ring part of the pipe before tightening the flare nut. And the fla-
re nut must be tightened using two spanners according to the
tightening torque as shown in the figure below. The tightening
work will be easier if tightening the flare pipe in order of the
liquid pipe, the gas pipe. Check the leakage of the refrigerant
after the tightening work.
N O T E
Refrigerant oil is field-supplied.
[ Ethereal Oil FVC50K, FVC68D (Idemitsu Kousan Co. Ltd.) ]
Apply refrigerant oil
Do not apply the
refrigerant oil to
the outside of the
flaring part.
Required tightening torque
Pipe size
Ø6.35 (1/4)
Ø9.52 (3/8)
Ø12.7 (1/2)
Ø15.88 (5/8)
29 PMML0292A rev.2 - 09/2015 - P5416572
mm (in.)
+0
A
Diameter (Ød)
-0.4
6.35 (1/4) 9.1
9.52 (3/8) 13.2
12.7 (1/2) 16.6
15.88 (5/8) 19.7
(JIS B8607)
Tightening torque
14 - 18 (N-m)
34 - 42 (N-m)
49 - 61 (N-m)
68 - 82 (N-m)
C A U T I O N
Tighten the flare nuts according to the specified torque. If not, it
may cause the refrigerant leakage.
5 When on-site piping with joint such as elbow, socket is buried,
provide a service access door to facilitate the check for con-
necting part.
6 Perform to support for earthquake resistant to the pipes in
order not to damage by an external force.
7 Do not clamp tightly the refrigerant pipe when supporting for
prevention of heat stress.
8 Do not touch the refrigerant pipes to low strength portions of
walls or ceilings. If not, it may cause abnormal sound or vi-
bration.
9 Perform the air tight test. The air tight procedures should be
performed according to "Installation and Operation Manual" of
the outdoor unit.
10 Insulate each flare connection without gap to prevent of dew
condensation by using the accessory thermal insulation pipe.
Additionally, insulate field gas and liquid pipings by using field-
supplied thermal insulations.
Insulation for Indoor Piping Connection
Wrap the accessory thermal insulation pipe around the flare con-
nection and fix it by tape as shown in the figure below:
Thermal insulation pipe
(Accessory)
11 For left side piping perform the fo-
llowing piping connection work.
a. It is recommended that the piping
connection work be performed by
2 people: one supports the indoor
unit and another performs the pi-
ping connection.
b. Prepare the L-shaped pipe before
the indoor unit is hung onto the
wall.
C A U T I O N
• Pay attention not to unhook the indoor unit from the suspen-
sion bracket.
• Do not apply excessive force to the flare nut when tightening.
If applied, the flare nut may crack due to aged degradation
and refrigerant leakage may occur. Use the specified tighte-
ning torque.