English
10
6. REFRIGERANT PIPING WORK
〈
For refrigerant piping of outdoor units, see the installation manual attached to the outdoor unit.
〉
〈
Execute heat insulation work completely on both sides of the gas piping and the liquid piping. Otherwise, a
water leakage can result sometimes.
〉
(
When using a heat pump, the temperature of the gas piping can reach up to approximately 120°C, so use
insulation which is sufficiently resistant.)
〈
Also, in cases where the temperature and humidity of the refrigerant piping sections might exceed 30°C or
RH80%, reinforce the refrigerant insulation. (20mm or thicker) Condensate may form on the surface of the
insulating material.
〉
〈
Be sure to check the type of R410A refrigerant to be used before doing any work. (Using an incorrect refrig-
erant will prevent normal operation of the unit.)
〉
CAUTION
•
Use a pipe cutter and flare suitable for the type of refrigerant.
•
Apply ester oil or ether oil around the flare section before connecting.
•
To prevent dust, moisture or other foreign matter from infiltrating the tube, either pinch the end or cover
it with tape.
•
Do not allow anything other than the designated refrigerant to get mixed into the refrigerant circuit, such
as air, etc. If any refrigerant gas leaks while working on the unit, ventilate the room thoroughly right away.
• Do not mix air or other gas with the specified refrigerant in the refrig-
eration cycle.
• Ventilate the room if refrigerant gas leaks during the work.
•
The outdoor unit is charged with refrigerant.
•
Be sure to use both a spanner and torque wrench together, as shown in the
drawing, when connecting or disconnecting pipes to/from the unit.
(Refer to Fig. 14)
•
Refer to “Table 3” for the dimensions of flare nut spaces.
•
When connecting the flare nut, apply ester oil or ether oil to the flare
section (both inside and outside), and spin 3-4 times before screw-
ing in.
(Refer to Fig. 15)
• Keep all the screw mounting resin parts (e.g., piping presser
plates) away from oil.
If oil adheres, the strength of the screw mounting resin parts may
drop.
CAUTION
Over-tightening the flare nut may break it and/or cause the
refrigerant to leak.
NOTE
•
Use the flare nut included with the unit main body.
Table 3
•
Refer to “Table 3” to determine the proper tightening torque.
Pipe size
Tightening torque
Flare dimensions
A (mm)
Flare
φ
6.4 (1/4”)
14.2 – 17.2N·m
8.7 – 9.1
φ
9.5 (3/8”)
32.7 – 39.9N·m
12.8 – 13.2
φ
12.7 (1/2”)
49.5 – 60.3N·m
16.2 – 16.6
φ
15.9 (5/8”)
61.8 – 75.4N·m
19.3 – 19.7
Torque wrench
Spanner
Pipe union
Flare nut
Fig. 14
Fig. 15
Coat here with ester or ether oil.
A
45
0
Ⳳ
2
0
R0.4-0.8
90
0
Ⳳ
2
0
01_EN_3P161684-4E.fm Page 10 Monday, August 16, 2010 7:11 PM
