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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
Ćø6.35 (1/4")
Ćø9.52 (3/8")
Ćø12.7 (1/2")
Ćø15.88 (5/8")
14 ā 18 N Ā· m
{140 ā 180 kgf Ā· cm}
34 ā 42 N Ā· m
{340 ā 420 kgf Ā· cm}
49 ā 55 N Ā· m
{490 ā 550 kgf Ā· cm}
68 ā 82 N Ā· m
{680 ā 820 kgf Ā· 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
Ćø6.35 (Liquid side)
Ćø9.52 (Liquid side)
Ćø12.7, Ćø15.88 (Gas side)
10.7 ā 14.7 N Ā· m {107 ā 147 kgf Ā· cm}
14.0 ā 20.0 N Ā· m {140 ā 200 kgf Ā· cm}
20.6 ā 28.4 N Ā· m {206 ā 284 kgf Ā· cm}
48.0 ā 59.8 N Ā· m {480 ā 598 kgf Ā· cm}
Valve stem cap
SM830231-02īSingleī꬧å·.indbīīī282SM830231-02īSingleī꬧å·.indbīīī282 2014/09/19īīī13:21:462014/09/19īīī13:21:46