English
7
Table 1
•
When connecting the flare nut, coat the flare section (both
inside and outside) with ester oil or ether oil, rotate three or
four times first, then screw in.
(Refer to Fig. 12)
•
Refer to the “Table 1” for tightening torque.
CAUTION
Over-tightening may damage the flare and cause a
refrigerant leakage.
•
If a torque wrench is not available, tighten the nut in the fol-
lowing manner. Once work is complete, make sure there is
no gas leaking. As the flare nut is tightened with the wrench,
the torque will suddenly increase. From that position, tighten
the nut to the angle shown on “ Table 2 ”.
Table 2
•
After the work is finished, make sure to check that there is no
gas leak.
•
After checking the pipe-connection for gas leakage, be sure
to insulate the liquid and gas piping.
(Refer to Fig. 13)
CAUTION
Be sure to insulate any field piping all the way to the piping
connection inside the unit. Any exposed piping may cause
condensation or burns if touched.
•
Connect refrigerant piping and branching according to the
attached installation manuals that come with the outdoor unit.
•
When brazing the refrigerant piping, perform nitrogen
replacement first, or perform the brazing (note 2) while
feeding nitrogen into the refrigerant piping (note 1), and
finally connect the indoor unit using the flare connections.
(Refer to Fig. 14)
CAUTION
•
When brazing a pipe while feeding nitrogen inside the pipe,
make sure to set the nitrogen pressure to 0.02 MPa
(0.2 kg/cm
2
) or less using the pressure reducing valve.
(This pressure is such that breeze is blown to your cheek.)
•
Do not use a flux when brazing the refrigerant pipe joints.
Use phosphor copper brazer (BCuP-2: JIS Z 3264/B-
Cu93P-710/795: ISO 3677) which does not require flux.
(Using a flux containing chlorine may cause the piping to
corrode. Using a welding flux containing fluorine may
cause the refrigerant lubricant to deteriorate, and affect
adversely the refrigerant piping system.)
•
Do not use anti-oxidants or other similar agent when braz-
ing the pipe joints.
Residue can clog the pipes and may cause breakdown of
parts.
8
DUCT CONNECTION
〈〈〈〈
Perform duct work keeping the following things in mind
〉〉〉〉
•
Do not connect the ducts as shown in Fig. 15.
•
The minimal radius of bends for flexible ducts are as follows.
200-mm duct : 300 mm diameter
250-mm duct : 375 mm diameter
•
To prevent air leakage, wind aluminum tape round the sec-
tion after the duct connecting flange and the duct are con-
nected.
(Refer to Fig. 16)
•
To prevent short circuit, install the opening of the indoor air
intake as far as from the opening of the exhaust suction.
Pipe
gauge
Tightening torque
Flare dimen-
sion A (mm)
Flare shape
φ
6.4
14.2–17.2 N·m
8.7 – 9.1
φ
12.7
49.5–60.3 N·m
16.2 – 16.6
Pipe size
Further tightening angle
Recommended arm
length of tool
φ
6.4 (1/4”)
60 to 90 degrees
Approx. 150mm
φ
12.7 (1/2”)
30 to 60 degrees
Approx. 250mm
A
45
0
Ⳳ
2
0
R0.4-0.8
90
0
Ⳳ
2
0
Torque wrench
Spanner
Piping union
Flare nut
Fig. 11
Ester oil or ether oil
Fig. 12
Gas Piping Insulation Procedure
Liquid Piping Insulation Procedure
Clamp
(accessory)
Clamp
(accessory)
Flare nut
connection
Piping insulation material
(locally procured)
Flare nut
connection
Turn seams up
Mid sealing pad
Wrap over the
top of the flare
nut connection.
(accessory)
Turn seams up
Piping insulation
material
(Locally procured)
Piping insulation
material
(main unit)
Piping insulation
material
(main unit)
Attach to base
Attach to base
Main unit
Main unit
Insulation for fitting
(accessory)
Insulation for fitting
(accessory)
Gas pipe
Liquid
pipe
Fig. 13
Model
Gas piping
diameter
Liquid piping
diameter
VKM50GMV1, VKM50GV1
VKM80GMV1, VKM80GV1
VKM100GMV1, VKM100GV1
φ
12.7
φ
6.4
Refrigerant piping
Part to be
brazed
Taping
Pressure-
reducing valve
hands
valve
Nitrogen
Nitrogen
Fig. 14
(a) Exterme bend
(b) Multi bend
(d) a bend right
next to the
outlet
(Do not reduce the duct
diameter halfway.)
(c) Reduce the
diameter of the
duct to be
connected.
Fig. 15
(Do not bend the
duct over 90˚)
01_3P130768-1A_En.fm Page 7 Wednesday, March 23, 2005 7:00 PM
