Daikin FUQ71CVEB Installation Manual page 18

Insulate the piping in the same
manner as shown in Fig. 22
using the attached joint
insulating material (6).
(e.g. Insulate the piping in the
same manner for upward
and rightward piping.)
(To prevent small animals and insects getting into the indoor unit, make sure to tightly fit the piping pen-
etrating cover to the casing and seal the clearance between the piping and the hole with putty and insu-
lating material (field supply).)
• Before brazing refrigerant piping, have nitrogen flow through the refrigerant piping and substitute air with
nitrogen (NOTE 1). (Refer to Fig. 24) Then, carry out brazing (NOTE 2).
After all the brazing works are finished, carry out flare connection with the indoor unit. (Refer to Fig. 21)
Refrigerant piping
NOTE
1. The proper pressure for having nitrogen flow through the piping is approximately 0.02MPa, a pressure
that makes one feel like breeze and can be obtained through a pressure reducing valve.
2. Do not use flux when brazing refrigerant piping.
Use phosphor copper brazing filler metal (BCuP-2: JIS Z 3264/B-Cu93P-710/795: ISO 3677) that does
not require flux.
(If chlorinated flux is used, the piping will be corroded and, in addition if fluorine is contained, the refrig-
erant oil will be deteriorated and the refrigerant circuit will be affected badly.)
3. When carrying out leakage test of refrigerant piping and the indoor unit after the installation of indoor unit
is finished, confirm the connecting outdoor unit installation manual for test pressure.
Refer to also the outdoor unit installation manual or technical document for refrigerant piping.
4. In case of refrigerant shortage due to forgetting additional refrigerant charge etc., it will result in malfunc-
tion such as does not cool or does not heat.
Refer to the outdoor unit installation manual or technical document for refrigerant piping.
CAUTION
Do not use antioxidant when brazing piping.
It may result in malfunction of components and clogging of piping due to residue.
17
Fig. 23
Brazing
place
Nitrogen
Fig. 24
For upward and rightward piping
L-shaped piping insulating method
Piping insulating material
(field supply)
To prevent sweating,
do not expose the piping
to the atmosphere.
Joint insulating
material (6)
(accessory)
Clamp (4)
(accessory)
Tighten the section where the piping insulating
material and the joint insulating material (6)
overlap.
Taping
Pressure reducing valve
Nitrogen
Stop valve
Flare nut
connection
L-shaped
piping (13)
English