Daikin VRV III Manual page 445

Installation
Refrigerant Piping Work
<For refrigerant piping between outdoor unit and this unit, see the installation manual attached to the
outdoor unit. (Refer to Table 1)>
<Execute heat insulation work completely on both sides of the gas pipe and the liquid pipe. Otherwise, a
water leakage can result sometimes.>
<When using a heat pump, the temperature of the gas pipe can reach up to approximately 120°C, so use
insulation which is sufficiently resistant.>
<Improve the insulation on the refrigerant piping depending on the installation environment. If the insulation
is not sufficient, condensate may form on the surface of the insulation.>
<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. (Refer to Fig. 7)
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.
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. 8)
Refer to Table 2 for the dimensions of flare nut spaces.
When connecting the flare nut, apply ether oil or ester oil only to inner side of the flare, rotate three or four times
first, then screw in. (Refer to Fig. 7)
Refer to Table 2 for tightening torque.
Table 1
Unit to be connected Gas pipe diameter
FXMQ125MFV1
FXMQ200MFV1 19.1 Use attached pipe.
FXMQ250MFV1 22.2 Use attached pipe.
Note:
Use the flare nuts attached with the unit.
CAUTION
Over-tightening may damage the flare and cause a refrigerant leakage.
Apply ester oil or ether oil only
to inner side of the flare.
440
Liquid pipe
diameter
φ 9.5
15.9
φ 9.5
φ 9.5
Fig. 7
Table 2
Flare dimen-
Pipe
Tightening torque sions
size
A (mm)
φ 9.5
32.7 – 39.9N·m
12.8 – 13.2
(3/8") (333 – 407 kgf·cm)
φ 15.9
61.8 – 75.4N·m
19.3 – 19.7
(5/8") (630 – 770 kgf·cm)
Torque wrench
Spanner
Piping union
Flare nut
Fig. 8
: http://splitoff.ru/tehn-doc.html
ED34-862
Flare shape
R0.4-0.8
FXMQ-MF