Daikin Sky Air B-Series R-410A, Service Manual, Page: 46 / 338

Si21-205 Field Piping and Wiring
Field Piping and Wiring 35
1.2 Refrigerant Piping, Drain Piping, and Wiring for FFQ
Model
1.2.1 Refrigerant Piping Work For FFQ Model
<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. (20 mm or thicker)
Condensation may form on the surface of the insulating material.>
<Before refrigerant piping work, check which type of refrigerant is used. Proper
operation is not possible if the types of refrigerant are not the same.>
Caution Use a pipe cutter and flare suitable for the type of refrigerant.
Apply ester oil or ether oil around the flare portions 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.
Note:
•
Use the flare nut included with the unit main body.
Table 3
•
Refer to “Table 3” to determine the proper tightening torque.
Caution Over-tightening may damage the flare and cause a refrigerant leakage.
•
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. 13)
•
Refer to
“
Table 3
”
for the dimensions of flare nut
spaces.
•
When connecting the flare nut, coat the flare section
(both inside and outside) with ester oil or ether oil,
rotate three or four times first, then screw in.
(Refer to Fig. 14)
Caution Over-tightening may damage the flare and cause a
refrigerant leakage.
Torque wrench
Flare nut
Piping union
Spanner
Fig. 13
Fig. 14
Pipe size Tightening torque
Flare dimensions
A (mm)
Flare
φ
6.4 (1/4
"
)
14.2 - 17.2 N·m
(144 - 175 kgf·cm)
8.7-9.1
φ
9.5 (3/8
"
)
32.7 - 39.9 N·m
(333 - 407 kgf·cm)
12.8-13.2
φ
12.7 (1/2
"
)
49.5 - 60.3 N·m
(505 - 615 kgf·cm)
16.2 - 16.6