NOTE
When reaming, hold the tube end downward and be sure that no copper scraps fall into the tube. (Fig. 9)
(3)Remove the flare nut from the unit and be sure to mount it on the copper tube.
(4)Make a flare at the end of copper tube with a flare tool.* (Figs. 10 and 11)
(*Use “RIDGID” or equivalent.)
NOTE
A good flare should have the following characteristics:
inside surface is glossy and smooth.
edge is smooth.
tapered sides are of uniform length.
a)Be sure to apply a sealing cap or
b)Be sure to apply refrigerant lubricant to the matching surfaces of the flare and union before connecting them together. This is effective for reducing gas leaks.
(Fig. 12)
c)For proper connection, align the union tube and flare tube straight with each other, then screw in the flare nut lightly at first to obtain a smooth match. (Fig. 13)
Copper tubing
Reamer
| Fig. 9 |
If the special R410A | If the previous flare tool |
flare tool is used: | |
0 to 0.0196" | 0.0472" (1.2 mm) |
(0 to 0.5 mm) | Adjust so that the amount of tube |
| |
| protrusion is as shown in the figure. |
Fig. 10
Flare nut
Copper 
tubing
Flare tool
Fig. 11
Apply refrigerant lubricant here and here
3-5. Tubing Connections
a)Temporary connection:
Screw in 3 – 5 turns by hand. (Fig.14)
b)To fasten the flare nuts, apply specified torque as:
Table 4
Tube Dia. | Nut | Tightening Torque |
|
|
|
1/4" (6.35 mm) | 21/32" (17 mm) | Approx. 120 – 160 lbs·in (140 – 180 kgf·cm) |
|
|
|
3/8" (9.52 mm) | 7/8" (22 mm) | Approx. 300 – 360 lbs·in (340 – 420 kgf·cm) |
|
|
|
1/2" (12.70 mm) | Approx. 430 – 480 lbs·in (490 – 550 kgf·cm) | |
|
|
|
5/8" (15.88 mm) | Approx. 590 – 710 lbs·in (680 – 820 kgf·cm) | |
|
|
|
Service valve on narrow tube side
Service valve on wide tube side
Fig. 14
Fig. 12
Union | Flare nut |
Fig. 13
D
C 
B 
A
Apply the provided labels to the indoor and outdoor unit tubing connectors to prevent errors in connections.
17
