<Tightening connection>
Align the centers of the connecting pipes and tighten the flare nut as far as possible with your fingers. Then tighten the nut with a spanner and torque wrench as shown in the figure.
CAUTION
•Do not apply excess torque. Otherwise, the nut may crack depending on the conditions.
(Unit : N•m) |
9-7-3. Pipe Shield for Flare Nut Connection
Joints in liquid and gas pipes of the indoor unit should be insulated with an attached Pipe shield $.
<How to install the pipe shield>
1.Cut the Pipe shield $ to appropriate length.
2.Set the Pipe shield $.
3.In case of a ceiling installation, orient the slit at the top of the pipe.
4.Fix the Pipe shield $ with vinyl tape.
Outer diam. of copper pipe | Tightening torque |
6.35 mm (diam.) | 14 to 18 (1.4 to 1.8 kgf•m) |
|
|
9.52 mm (diam.) | 33 to 42 (3.3 to 4.2 kgf•m) |
|
|
12.7 mm (diam.) | 50 to 62 (5.0 to 6.2 kgf•m) |
Vinyl tape
Slit
15.9 mm (diam.) | 63 to 77 (6.3 to 7.7 kgf•m) |
•Tightening torque of flare pipe connections
Pressure of R410A becomes higher than that of R22. (Approx. 1.6 times) Therefore, using a torque wrench, tighten firmly the flare pipe connecting sections which connect the indoor and outdoor units up to the specified tightening torque.
Incorrect connections may cause not only a gas leakage, but also a trouble of the refrigeration cycle or compressor damage.
Flare at
indoor unit side
| Flare at |
| outdoor unit side |
| Fig. |
Half union | Flare nut |
Externally | Internally |
threaded side | threaded side |
Use a wrench to secure. | Use a torque wrench to tighten. |
Fig.
$Pipe shield
Fig.
– 38 –
