-
-
'13 • SRK-T-144
Determine refrigerant pipe size pursuant to the following guidelines based on
the indoor unit specifications.
Without nitrogen gas, a large quantity of foreign matters
(oxidized film) are created, causing a critical failure from
capillary tube or expansion valve clogging.
2. REFRIGERANT PIPING WORK
1) Restrictions on unit installation and use
2) Determination of pipe size
15m or less
10m or less
10m or less
L
H
H
L
H
Outdoor unit
Indoor unit
The use restrictions appearing in the table above are applicable to the standard pipe size combinations shown in the table below.
Restrictions
Model SRC20~35/DXC09,12
Marks appearing in the
drawing on the right
Main pipe length
When the outdoor unit is positioned higher,
When the outdoor unit is positioned lower,
Elevation difference between
indoor and outdoor units
Plug the end of the pipe with tape, or other
material, and fill the pipe with nitrogen gas.
Only use nitrogen gas (N
2
)
Taping
<N2>
Nitrogen
Brazing
Station valve
Primary side
Secondary side
0.5MPa
Hand
Relief valve
Nitrogen
gas
Brazing must be performed under a nitrogen gas flow.
About brazing
When pipe is brazing.
• Check the following points in light of the indoor unit specifications and the installation site.
• Observe the following restrictions on unit installation and use. Improper installation can result in a compressor failure or performance degradation.
• Additional refrigerant charge is not required at all (Model SRC20~35/DXC09,12).
25m or less
15m or less
15m or less
Dimensional restrictions
Model SRC50/DXC18
ø12.7
Flare
ø12.7
ø12.7
Gas pipe
ø6.35
Flare
ø6.35
ø6.35
Model SRC50/DXC18
Liquid pipe
ø9.52
Flare
ø9.52
ø9.52
Gas pipe
ø6.35
Flare
ø6.35
ø6.35
Model SRC20~35/DXC09,12
Liquid pipe
Outdoor unit connected
Refrigerant piping (branch pipe L)
Indoor unit connected
CAUTION
Take care so that installed pipes may not touch components within a unit.
If touching with an internal component, it will generate abnormal sounds and/or vibrations.
4) On-site piping work
IMPORTANT
How to remove the side cover
Please remove the screw of a side cover and
remove to the front.
A
B
Flared pipe end : A
(mm)
ø6.35
ø9.52
ø12.7
Copper pipe
outer diameter
0
A –04
9.1
13.2
16.6
ø6.35
ø9.52
ø12.7
Copper pipe
outer diameter
0
~
0.5
1.0
~
1.5
Copper pipe protrusion for flaring : B
(mm)
In the case of a rigid (clutch) type
With an R410A tool With a conventional tool
CAUTION
Do not apply force beyond proper fastening torque in tightening the flare nut.
Tightening angle (
o
)
Tightening torque (N·m)
ø6.35 (1/4")
ø9.52 (3/8")
ø12.7 (1/2")
Recommended length of a tool handle (mm)
Service valve size (mm)
Do not hold the valve cap area with a spanner.
3) Refrigerant pipe wall thickness and material
NOTE
*Phosphorus deoxidized seamless copper pipe ICS 23.040.15, ICS 77.150.30
ø6.35
0.8
O-type pipe
ø9.52
0.8
O-type pipe
ø12.7
0.8
O-type pipe
Pipe diameter [mm]
Minimum pipe wall thickness [mm]
Pipe material*
• Select refrigerant pipes of the table shown on the right wall thickness and material as specified
for each pipe size.
• Carry out the on site piping work with the service valve fully closed.
• Give sufficient protection to a pipe end (compressed and blazed, or with an
adhesive tape) so that water or foreign matters may not enter the piping.
• Bend a pipe to a radius as large as practical (R100~R150). Do not bend a pipe
repeatedly to correct its form.
• Flare connection is used between the unit and refrigerant pipe. Flare a pipe after
engaging a flare nut onto it. Flare dimensions for R410A are different from
those for conventional R407C. Although we recommend the use of flaring tools
designed specifically for R410A, conventional flaring tools can also be used by
adjusting the measurement of protrusion B with a protrusion control gauge.
• The pipe should be anchored every 1.5m or less to isolate the vibration.
• Tighten a flare joint securely.
Fix both liquid and gas service valves at the valve main bodies as illustrated on the right, and then fasten them,
applying appropriate fastening torque.
Select pipes having a wall thickness larger than the specified minimum pipe thickness.
14
~
18
34
~
42
49
~
61
45
~
60
30
~
45
30
~
45
150
200
250
Use a torque wrench. If a torque wrench is not
available, fasten the flare nut manually first and then
tighten it further, using the left table as a guide.
The screw of the
side cover is
tightened securely.
Side cover
