Drain Piping Work - Daikin FBQ24PVJU Installation Manual

(2) On completion of installation work, check that there is no
gas leakage.
(3) Refer to the following illustration and be sure to perform
thermal insulation work on the piping joints after gas leak-
age checks. (Refer to Fig. 6)
Thermal insulation procedure for liquid piping
Insulation for fitting (4) (accessory)
Insulation material
Flare nut joint
for piping
(on unit side)
Make sure that
the seam faces
Attached to
upward.
the surface.
Main unit
Clamp (8)
(accessory)
Insulation material
for piping (field supply)
Gas pipe
Thermal insulation procedure for gas piping
Insulation for fitting (5) (accessory)
Insulation material
Flare nut joint
for piping
(on unit side)
Make sure that
the seam faces
Attached to
upward.
the surface.
Clamp (8)
(accessory)
Insulation material
for piping (field supply)
• Use the insulation for fitting (4) and (5) provided to the
liquid piping and gas piping, respectively, and conduct
thermal insulation work.
(Tighten both edges of the insulation for fitting (4) and (5)
for each joint with the clamp (8).)
• Make sure that the joint of the insulation for fitting (4) and
(5) for the joint on the liquid piping and gas piping side
faces upward.
• Wrap the middle sealing material (7) around the insula-
tion for fitting (4) and (5) for the joint (flare nut part).
English
Middle sealing pad (7)
(accessory)
Wrap the insulation material
around the portion from the
surface of the main unit to the
upper part of the flare nut joint.
Liquid pipe
Fig. 6
Middle sealing pad (7)
(accessory)
Wrap the insulation material
around the portion from the
surface of the main unit to the
upper part of the flare nut joint.
CAUTION
• Be sure to perform the thermal insulation of the local pip-
ing up to the piping joint.
If the piping is exposed, dew condensation may result. Fur-
thermore, a burn may be caused if a human body comes in
contact with the piping.
• Perform nitrogen substitution or apply nitrogen into the
refrigerant piping (see NOTE 1) in the case of refrigerant
piping brazing (see NOTE 2). Then perform the flare con-
nection of the indoor unit. (Refer to Fig. 7)
Refrigerant
piping
Part to be
brazed
Nitrogen
Fig. 7
CAUTION
• Do not use any antioxidant at the time of piping brazing.
The piping may be clogged with a residual antioxidant and
parts may malfunction.
NOTE
1. At the time of brazing, set the pressure of nitrogen to
approximately 2.9 PSI (0.02 MPa) (close to the pressure
of a breeze coming in contact with the cheek) with a pres-
sure-reducing valve.
2. Do not use flux at the time of brazing and connecting the
refrigerant piping. Use a copper phosphorus brazing alloy
(BCuP-2/BCu 93P-710/795), which does not require flux,
for brazing.
(Flux has a bad influence on the refrigerant piping. Chlo-
rine-based flux will cause piping corrosion. Furthermore, if
it contains fluorine, the flux will deteriorate refrigerant oil.)
7.

DRAIN PIPING WORK

(1) Conduct drain piping work.
Check that the piping
ensures proper draining.
• Make sure that the diam-
eter of the piping exclud-
ing the rising part is the
same as or larger than
the diameter of the con-
necting pipe (vinyl chloride pipe with an outer diameter
of 1-1/4 in. (32 mm) and a nominal inner diameter of 1 in.
(25 mm)).
• Make sure that the piping is short enough with a down-
ward slope of at least 1/100 and that there is no air
bank formed. No drain trap is required.
Pressure-reducing valve
Taping
hand
valve
Nitrogen
Refrigerant
piping
Drain socket
Socket for
maintenance
(with rubber cap)
8