![background image](http://html1.mh-extra.com/html/daikin/rweq96tayd-series/rweq96tayd-series_installation-manual_4699714011.webp)
4 Preparation
Installation manual
11
RWEQ96~432TAYD
∗
+ RWEQ96~432TATJ
∗
VRV W T-Series water-cooled system air conditioner
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 31.
"6 Checking of device and installation conditions" on
page 35 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
D
E
E
E
E
x
y
b
a
1
2
3
4
b
1~4
VRV indoor unit
A~E
Piping
a,b
Indoor branch kit
x,y
Outside multi connection kit
In case of heat recovery mode
A
B
B
B
C
D
E
D*
D
D
x
y
b
a
2
12
3
4
5
6
1
7
8
9
1
E
E
b
E
E
E
E
E
10
11
E
E
b
1
Multi branch selector unit
2
Single branch selector unit
3~11
VRV indoor unit
12
Cooling only VRV indoor unit
A~E
Piping
a,b
Indoor branch kit
x,y
Outside multi connection kit
01_EN_4P602454-1C.indd 11
2020/07/29 16:16:39