English
8
6. REFRIGERANT PIPING WORK
〈〈〈〈
For refrigerant piping of outdoor unit and BP unit, see the installation manuals attached to the out-
door unit and BP 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. (20 mm or thicker) Condensate may form on the surface of the
insulating material.
〉
〈
Be sure to check the type of refrigerant to be used before doing any work. (Using an incorrect refrigerant 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.
•
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. 6)
•
Refer to “Table 1” 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 screwing
in.
(Refer to Fig. 7)
NOTE
•
Use the flare nut included with the unit main body.
Table 1
•
Refer to “Table 1” to determine the proper tightening torque.
CAUTION
Over-tightening the flare nut may break it and/or cause the refrigerant to leak.
Pipe size
Tightening torque
Flare dimensions
A (mm)
Flare
φ
6.4
14.2 – 17.2N·m (144 – 176 kgf·cm)
8.7 – 9.1
φ
9.5
32.7 – 39.9N·m (333 – 407 kgf·cm)
12.8 – 13.2
φ
12.7
49.5 – 60.3N·m (504 – 616 kgf·cm)
16.2 – 16.6
φ
15.9
61.8 – 75.4N·m (630 – 770 kgf·cm)
19.3 – 19.7
Torque wrench
Spanner
Pipe union
Flare nut
Fig. 6
Coat here with ester or ether oil
Fig. 7
R0.4-0.8
A
90
0
±
0.5
0
45
0
±
2
0
01_EN_3P156215-4C.fm Page 8 Saturday, May 14, 2005 9:17 AM
