Panasonic S-200PE2E5 Technical Data & Service Manual page 51

Caution Before Connecting Tubes Tightly
(1) Apply a sealing cap or water-proof tape to prevent dust or
water from entering the tubes before they are used.
(2) Be sure to apply refrigerant lubricant (ether oil) to the
inside of the flare nut before making piping connections.
This is effective for reducing gas leaks. (Fig. 1- 22)
(3) For proper connection, align the union tube and flare tube
straight with each other, then screw on the flare nut lightly
at first to obtain a smooth match. (Fig. 1- 23)
Adjust the shape of the liquid tube using a tube bender
at the installation site and connect it to the liquid
tubing side valve using a flare.
Cautions During Brazing
Replace air inside the tube with nitrogen gas to prevent copper oxide film from forming during the
brazing process. (Oxygen, carbon dioxide and Freon are not acceptable.)
Do not allow the tubing to get too hot during brazing.
The nitrogen gas inside the tubing may overheat, causing refrigerant system valves to become damaged.
Therefore allow the tubing to cool when brazing.
Use a reducing valve for the nitrogen cylinder.
Do not use agents intended to prevent the formation of oxide film.
These agents adversely affect the refrigerant and refrigerant oil, and may cause damage or malfunctions.
2. Connecting Tubing Between Indoor and Outdoor Units
(1) Tightly connect the indoor-side refrigerant tubing extended
from the wall with the outdoor-side tubing.
(2) To fasten the flare nuts, apply specified torque.
When removing the flare nuts from the tubing connections,
or when tightening them after connecting the tubing, be sure
to use a torque wrench and a spanner. (Fig. 1- 24)
If the flare nuts are over-tightened, the flare may be damaged,
which could result in refrigerant leakage and cause injury or
asphyxiation to room occupants.
For the flare nuts at tubing connections, be sure to use the
flare nuts that were supplied with the unit, or else flare nuts
for R410A (Type 2). The refrigerant tubing that is used must
be of the correct wall thickness as shown in the table.
Because the pressure is approximately 1.6 times higher than
conventional refrigerant pressure, the use of ordinary flare
nuts (Type 1) or thin-walled tubes may result in tube rupture,
injury, or asphyxiation caused by refrigerant leakage.
In order to prevent damage to the flare caused by
overtightening of the flare nuts, use the table as a guide
when tightening.
When tightening the flare nut on the liquid tube, use an
adjustable wrench with a nominal handle length of 200 mm.
Apply refrigerant lubricant.
Indoor Unit Tubing Connection (
Indoor unit type
Gas tubing (mm)
Liquid tubing (mm)
Indoor unit
Tube
diameter
ø6.35 (1/4")
ø9.52 (3/8")
ø12.7 (1/2")
ø15.88 (5/8")
ø19.05 (3/4")
1-45
Fig. 1- 22
Flare nut
Union
Fig. 1- 23
,
1 2
200 250
ø25.4 ø25.4
ø9.52 ø12.7
Torque wrench
Spanner
Outdoor unit
Fig. 1- 24
Tightening torque Tube
(approximate)
thickness
14 – 18 N · m
0.8 mm
{140 – 180 kgf · cm}
34 – 42 N · m
0.8 mm
{340 – 420 kgf · cm}
49 – 61 N · m
0.8 mm
{490 – 610 kgf · cm}
68 – 82 N · m
1.0 mm
{680 – 820 kgf · cm}
100 – 120 N · m
1.0 mm
{1000 – 1200 kgf · cm}
1
)
...
n-1