Panasonic U-100PEY1E5, Technical Data & Service Manual, Page: 319 / 739

1
1-309
Precautions for Packed Valve Operation
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 below.
In order to prevent damage to the flare caused by overtightening of the flare nuts, use the table above as a
guide when tightening.
When tightening the flare nut on the liquid tube, use a adjustable wrench with a nominal handle length of
200 mm.
When tightening the flare nut with the adjustable wrench, do not apply to the valve stem cap with the other
one. If doing so, the valve will be damaged.
Depending on the installation conditions, applying excessive torque may cause the nuts to crack.
If the packed valve is left for a long time with the valve stem
cap removed, refrigerant will leak from the valve.
Therefore, do not leave the valve stem cap removed.
Use a torque wrench to securely tighten the valve stem cap.
Tightening torque:
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.
Tube diameter
Tightening torque
(approx.)
Tube thickness
ø6.35 (1/4")
ø9.52 (3/8")
ø12.7 (1/2")
ø15.88 (5/8")
14 – 18 N · m
{140 – 180 k
g
f · cm}
34 – 42 N · m
{340 – 420 k
g
f · cm}
49 – 55 N · m
{490 – 550 k
g
f · cm}
68 – 82 N · m
{680 – 820 k
g
f · cm}
0.8 mm
0.8 mm
0.8 mm
1.0 mm
Flare nut
Valve stem cap
Packed valve
Charging port
Valve stem
Main valve
Valve stem cap
Tightening torque (approx.)
Charging port
ø6.35 (Liquid side)
ø9.52 (Liquid side)
ø12.7, ø15.88 (Gas side)
10.7 – 14.7 N • m {107 – 147 k
g
f • cm}
14.0 – 20.0 N • m {140 – 200 k
g
f • cm}
20.6 – 28.4 N • m {206 – 284 k
g
f • cm}
48.0 – 59.8 N • m {480 – 598 k
g
f • cm}
Va
lv
e st
em
c
ap
SM830211-07̲PAC-i.indb 309 SM830211-07̲PAC-i.indb 309 2013/09/17 22:48:02 2013/09/17 22:48:02