Daikin FBQ20DAVMK, Installation Manual

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English 13
• Nitrogen should be set to 0.02MPa with a pressure-reducing valve if brazing while inserting nitrogen into
the piping.
(Refer to Fig. 9)
• Do not use flux when brazing refrigerant piping. Therefore, use the phosphor copper brazing filler metal
(BCuP-2: JIS Z 3264/B-Cu93P-710/795: ISO 3677) which does not require flux.
(Flux has extremely harmful influence on refrigerant piping systems. For instance, if the chlorine based flux is
used, it will cause pipe corrosion or, in particular, if the flux contains fluorine, it will damage the refrigerant oil.)
• When the airtight test is performed for the indoor unit and inter-unit piping after indoor unit installation, be
sure to refer to the installation manual for the indoor unit or technical guide for airtight pressurization and
refrigerant piping installation.
• Shortage of refrigerant due to air purge or losing the additional refrigerant charging may cause the failure
of the unit (does not sufficiently cool or heat).
Be sure to refer the installation manual or the engineering guide for the outdoor unit at the refrigerant piping
work.
CAUTION
• Do not use anything such as the oxidation inhibitor when brazing. (Residues may result in the clogging pipe
or parts damage.)
7. DRAIN PIPING WORK
(1) Remove the drain socket cover. (for transportation)
(2) Conduct drain piping work.
Check that the piping ensures proper draining.
• Make sure that the diameter of the piping excluding the rising
part is the same as or larger than the diameter of the
connecting pipe (vinyl chloride pipe with an outer diameter
of 32 mm and a nominal inner diameter of 25 mm).
• Make sure that the piping is short enough with a downward
slope of at least 1/100
and that there is no air bank formed.
No drain trap is required.
CAUTION
• The drain piping will be clogged with water and water leakage may result if the water is accumulated in the
drain piping.
• Conduct drain-up piping work if the gradient is insufficient.
• Attach some support brackets at 1 to 1.5 m intervals for the prevention of piping deflection.
• Be sure to use the drain hose (2) and metal clamp (1).
Insert the drain hose (2) deep into the base of the drain
socket, and securely fasten the metal clamp (1) within the
taped part on the insertion front end of the hose.
Be sure to fasten the screw of the metal clamp (1) until the
margin of the screw thread decreases to 4 mm or less.
Drain socket cover
(for transportation)
Drain socket
Refrigerant
piping
Screw (4 portions)
Supporting hanger
Downward slope of at least 1/100
1 - 1.5 m
(accessory)
Metal clamp (1)
Tape
(accessory)
Drain hose (2)
01_EN_3PN06583-10W.fm Page 12 Thursday, March 24, 2011 9:03 AM