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English
NOTE
1.
For the nitrogen exchange procedures, please refer to the Multi-split Type Series for Building installation
manual (contact your Daikin dealer).
2.
When brazing after having nitrogen flow through the pipe and substituting nitrogen for air, it is appropriate
to set the nitrogen pressure to about 0.02MPa with a pressure reducing valve.
(Refer to Fig. 16)
3.
Do not use flux when brazing refrigerant piping. Use the phosphor copper brazing filler metal (BCuP-2: JIS
Z 3264/B-Cu93P-710/795: ISO 3677) that does not require flux.
(Chlorine based flux is extremely harmful to refrigerant piping systems. It will corrode the refrigerant piping
and if it contains fluorine it will deteriorate the refrigerating oil.
4.
When performing the leakage test for the indoor unit and inter-unit piping after the indoor unit is installed,
be sure to refer to the installation manual for the indoor unit or technical guide for the leakage test pressure
and the refrigerant piping installation.
5.
Shortage of refrigerant due to air purge or forgetting the additional refrigerant charge may cause malfunc-
tion of the unit (does not sufficiently cool or heat).
For installation of refrigerant piping, be sure to refer to the installation manual for the outdoor unit or the
technical guide.
CAUTION
•
Do not use oxidation inhibitors or the like when brazing. (Residues may cause clogging of pipes or damage
to parts.)
7. DRAIN PIPING WORK
(1) Install the drain piping. (Refer to Fig. 17)
Perform the drain piping work so that water drains properly.
•
The drain piping should be short with a downward slope of 1/100 or more, and should prevent air pock-
ets from forming. The drain hose which is indoor units should also have a downward slope.
CAUTION
•
The drain pipe may be clogged if water accumulates in the drain pipe.
•
Watch out for the points in the Fig. 17 when performing drain work.
Refrigerant piping
Part to be
brazed
Taping
Pressure-reducing valve
hands valve
Nitrogen
Fig. 16
Nitrogen
Fig. 17
Make sure the drain
pipe is at a downward
slope.
Make sure the tip does
not go underwater even
when water is added.
Drain hose
Drain hose
(Downward
slope)
3P184443-9J_FM6.book Page 12 Wednesday, December 14, 2011 10:29 AM
