Daikin VRV W T-series - Operation Procedure

4 Preparation
Installation manual
11
RWEQ96~432TAYCU
VRV W T-Series water-cooled system air conditioner
4P540122-1B – 2018.11
4.3 Refrigerant pipe size and allowable
length
NOTE
The refrigerant R410A requires strict cautions for keeping
the system clean, dry and tight.
▪ Cleananddry:foreignmaterials(includingmineraloils
or moisture) should be prevented from getting mixed
into the system.
▪ Tight: R410A does notcontain any chlorine, does not
destroy the ozone layer, and does not reduce earth’s
protection against harmful ultraviolet radiation. R410A
can contribute slightly to the greenhouse effect if it is
released. Therefore we should take special attention to
check the tightness of the installation.
4.3.1 Selection of piping material
NOTE
Piping and other pressure containing parts shall comply
with the applicable legislation and shall be suitable for
refrigerant. Use phosphoric acid deoxidized seamless
copper for refrigerant.
NOTE
▪ All field piping must be installed by a licensed
refrigeration technician and must comply with relevant
local and national regulations.
▪ After piping work is complete, do not under any
circumstances open the stop valve until
"5.8 Connecting the electrical wiring" on page 30.
"6 Checking of device and installation conditions" on
page 34 are complete.
▪
Do not use flux when brazing the refrigerant piping. Use
the phosphor copper brazing filler metal
(B-Cu93P-710/795 : ISO 3677) which does not require
flux. Flux has extremely negative effect 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.
▪ Useonly pipeswhicharecleaninsideandoutside andwhich do
not accumulate harmful sulfur, oxidants, dirt, cutting oils, moisture,
or other contamination. (Foreign materials inside pipes including
oils for fabrication must be 0.14 gr/10 ft (30 mg/10 m) or less.)
▪ Usethefollowingitemsfortherefrigerantpiping.
Material : Jointless phosphor-deoxidized copper pipe.
Size : See "4.3.2 To select the piping size".
Thickness : Select a thickness for the refrigerant piping which
complies with national and local laws.
▪ Forpipingwork,followthemaximumtoleratedlength,differencein
height, and length after a branch indicated in the "4.3.7 Piping
length requirements" on page 15.
▪ Outsideunit multiconnection pipingkitand refrigerantbranch kit
(sold separately) are needed for connection of piping between
outside units (in case of multi system) and piping branches.
▪ Use only separately sold items selected specifically according to
the outside unit multi connection piping kit, the refrigerant branch
kit selection in the "4.3.3 To select refrigerant branch kits" on page
12.
4.3.2 To select the piping size
INFORMATION
Please select the proper pipe sizes depending on the
mode of your system. There are 2 possible modes:
▪ heatpump,
▪ heatrecovery.
Determine the proper size using the following tables and reference
figure (only for indication).
In case of heat pump mode
A
B B B
C
D F
G
E
x
y
b
a
1 2
3 4
b
1,2,3,4 VRV indoor unit
a,b Indoor branch kit
x,y Outside multi connection kit
In case of heat recovery mode
A
B B B
C
D E
E
x
y
b
a
4
3
1 2
1,2 VRV indoor unit
3 Branch selector unit
4 Cooling only VRV indoor unit
A~E Piping
a,b Indoor branch kit
x,y Outside multi connection kit
A, B, C: Piping between outside unit and (first)
refrigerant branch kit
Choose from the following table in accordance with the outside unit
total capacity type, connected downstream.
In case of heat pump mode
Unit: inch (mm)
Outside unit
capacity type (MBH)
Piping outer diameter size
Gas pipe Liquid pipe
96 7/8 (22.2) 3/8 (9.5)
120, 144 1-1/8 (28.6) 1/2 (12.7)
192, 216 5/8 (15.9)
240 1-3/8 (34.9)
264~336 3/4 (19.1)
360~432 1-5/8 (41.3)