Required tightening torque
(JIS B8607)
Pipe size
Tightening torque
Ø6.35 (1/4)
14 - 18 (N-m)
Ø9.52 (3/8)
34 - 42 (N-m)
Ø12.7 (1/2)
49 - 61 (N-m)
Ø15.88 (5/8)
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 connecting 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
vibration.
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
connection and fix it by tape as shown in the figure below:
Thermal insulation pipe
(Accessory)
11
For left side piping perform the
following 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 piping connection.
b.
Correctly position piping before
installing the indoor unit to the
wall. For left-rear side piping
connections refer to section
!
C A U T I O N
• Pay attention not to unhook the indoor unit from the suspension
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 tightening torque.
15 DRAIN PIPING
!
D A N G E R
Do not insert the drain pipe for the indoor unit to the drainage trench
where corrosive gases occur. Poisonous gases flow into the room,
so that may cause the poisoning.
?
N O T E
• Do not create an upper-slope or rise for the drain piping, since drain
water can flow back to the indoor unit and leakage into the room will
occur when the system operation is stopped.
• Do not connect the drain pipe with sanitary or sewage piping or any
other drainage piping.
• When the common drain piping is connected with other indoor units,
the connected position of each indoor unit must be higher than the
common piping. The pipe size of the common drain pipe must be
large enough according to the unit size and number of units.
• After performing drain piping work and electrical wiring, check to
ensure that water flows smoothly as in the following procedure.
1
The standard direction of drain piping connection is rear
side as viewed from the discharge grilles. However, it can be
performed from the left side of the unit
(VP16)
ɸ E
A
B
C
D
C
ɸ E
Exterior Contour for Indoor unit
Hole for
rear piping
Hole for rear piping
Condensate piping
connection
Unit: mm
HP
Dimension
0.4 to 1.0
1.5
2.0 to 4.0
A
638
657
925
B
568
568
550
C
45
45
51
D
107
107
120
E
65
65
80
Drain piping
PMML0552 rev.1 - 02/2021 - A10635790A
17
ENGLISH