Daikin RWEYQ72, Engineeiring Data

Page: 42 / 51

EDUS30-900-N Installation
Installation of Outdoor Units 41
•
The wall thickness of the refrigerant piping should comply with
relevant local and national regulations. For R410A the design
pressure is 550 psi.
3.
Make sure to use the particular branches of piping that have been
selected referring to chapter “Example of connection”.
4.
Refer to chapter “Stop valve operation procedure” in 9-10 about
the stop valve operation procedure.
5.
Make sure to perform the piping installation within the range of the
maximum allowable pipe length, allowable level difference and
allowable length after branching as indicated in chapter “Example
of connection”
6.
For installation of the refrigerant branching kit, refer to the installa-
tion manual delivered with the kit.
And follow the conditions listed below.
•
Mount the REFNET joint so that it branches either horizontally
or vertically.
•
Mount the REFNET header so that it branches horizontally.
(Refer to figure 22)
1.
Horizontal connections
2.
Up to ± 30° or vertically
3.
Horizontal connections
7.
To connect the piping between outside units, an optional piping kit
(multi connection piping kit) is always required. When installing the
piping, follow the instructions in the installation manual that comes
with the kit.
Restriction for the installation of the outside unit multi connec-
tion piping kit
• Install the joint horizontally within a lean of ±15° with caution
nameplate on top. Refer to figure 23 (Fig. A)
Do not connect it vertically. Refer to figure 23 (Fig. B)
• Reserve the straight part of 19-11/16 in. or more to the branch pipe
and do not bend the local pipe in that area.Straight part of 19-11/
16 in. or more can be reserved if a local pipe (straight pipe) of 4-3/
4 in. or more is connected to the joint. Refer to figure 23 (Fig. C)
• Incorrect installation may cause breakage of outside unit.
(Refer to figure 23)
1.
Caution nameplate
2.
Horizontal line
3.
Ground
4.
Straight part of 19-11/16 in. or more
5.
Local pipe
(4-3/4 in. length or more)
Precautions when selecting branch piping.
• If the overall equivalent length of piping between the outside units
and indoor units is 262.5 ft or more, be sure to enlarge the main
pipe in the liquid-side branch piping.
Depending on the length of the refrigerant piping, the cooling/heat-
ing capacity may drop, but even in such cases it is ok to enlarge
the main pipe.
(Refer to figure 21)
1.
Outside unit
2.
Main pipe
3.
Enlarge
4.
The first refrigerant branching kit.
5.
Indoor unit
[Liquid side]
RWEYQ72/84PTJU type:
 
3/8”
 
1/2”
RWEYQ144PTJU type:
 
1/2”
 
5/8”
RWEYQ168/216PTJU type:
 
5/8”
 
3/4”
RWEYQ252PTJU type:
 
3/4”
 
7/8”
9-2 Protection against contamination when
installing pipes
•
Take measures to prevent foreign materials like moisture and
contamination from mixing into the system.
•
Great caution is needed when passing copper tubes through
walls.
9-3 Pipe connection
•
Only use the flare nuts included with the unit.
Using different flare nuts may cause the refrigerant to leak.
•
Be sure to perform a nitrogen blow when brazing.
(Brazing without performing nitrogen replacement or releasing
nitrogen into the piping will create large quantities of oxidized
film on the inside of the pipes, adversely affecting valves and
compressors in the refrigerating system and preventing normal
operation.)
•
Do not use a flux when brazing the refrigerant pipe joints.
Use phosphor copper brazing (B-Cu93P-710/795: ISO 3677)
which does not require flux.
(Flux has an extremely negative effect on refrigerant piping
systems. For instance, if chlorine based flux is used, it will
cause pipe corrosion. If the flux contains fluorine, it will damage
the refrigerant oil.)
DANGER
•
Use of oxygen could cause an explosion resulting in severe inju-
ry or death. Only use nitrogen gas.
•
Refrigerant gas may produce toxic gas if it comes in contact with
fire such as from a fan heater, stove or cooking device. Exposure to
this gas could cause severe injury or death.
NOTE
•
The pressure regulator for the nitrogen released when doing the
brazing should be set to 2.9 psi or less.
(Refer to figure 18)
1.
Refrigerant piping
2.
Location to be brazed
3.
Nitrogen
4.
Taping
5.
Manual valve
6.
Regulator
Precautions when connecting pipes
• See the following table for flare part machining dimensions.
• When connecting the flare nuts, apply refrigerant oil to the inside of
the flares and turn them three or four times at first.
(Use ester oil or ether oil.)
• See the following table for tightening torque.
(Applying too much torque may cause the flares to crack.)
• After all the piping has been connected, check the gas leak with
nitrogen.
Not recommendable but in case of emergency
You must use a torque wrench but if you are obliged to install the unit
without a torque wrench, you may follow the installation method men-
tioned below.
After the work is finished, make sure to check that there is no gas
leak.
When you keep on tightening the flare nut with a spanner, there is a
point where the tightening torque suddenly increases. From that posi-
tion, further tighten the flare nut the angle shown below:
(Unit: in.)
Place Installation period Protection method
Outdoor
More than a month Pinch the pipe
Less than a month
Pinch or tape the pipe
Indoor Regardless of the period
pipe size
(in.)
tightening torque
(ft. · lbf)
A
(in.)
flare shape

3/8” 24.1 - 29.4 0.504 - 0.520

1/2” 36.5 - 44.5 0.638 - 0.654

5/8” 45.6 - 55.6 0.760 - 0.776
Pipe size Further tightening angle Recommended arm length of tool

3/8” 60 to 90 degrees Approx. 7-7/8

1/2”
30 to 60 degrees Approx. 9-13/16

5/8” 30 to 60 degrees Approx. 11-13/16

3/4”
20 to 35 degrees Approx. 17-3/4
R=0.016~0.031
45˚±2
90˚±2
A