Protection Of Pipes; Pipe Installation; Brazing; Indoor Unit Pipe Connections - Fujitsu Airstage AJYA72LALH Installation Manual

• Header
Total cooling capacity of indoor unit (kW)
28.0 or less
28.1 to 56.0
*5. For the installation method, refer to the section on "Indoor unit pipe connections"
below.
4. 3.

Protection of pipes

• Protect the pipes to prevent the entry of moisture and dust.
• Especially pay attention when passing the pipes through a hole or connecting the
end of a pipe to the outdoor unit.
Location Working period
1 month or more
Outdoor
Less than 1 month
—
Indoor
5.

PIPE INSTALLATION

5. 1.

Brazing

CAUTION
If air or different type of refrigerant enters
the refrigeration cycle, the internal pres-
sure in the refrigeration cycle will become
abnormally high and prevent the unit from
exerting its full performance.
Apply nitrogen gas while brazing the
pipes.
Nitrogen gas pressure: 0.02 MPa (= suf-
fi cient pressure to be felt on the back of
your hand or more)
If a pipe is brazed without applying nitrogen gas, it will create an oxidation fi lm.
This can degrade performance or damage the parts in the unit (such as the com-
pressor or valves).
Do not use fl ux to braze pipes. If the fl ux is the chlorine type, it will cause the pipes
to corrode.
In addition, if the fl ux contains fl uoride, it will affect the refrigerant piping system due to
deterioration of refrigerant oil.
For brazing material, use phosphor copper that does not require fl ux.
5. 2.

Indoor unit pipe connections

CAUTION
For details, refer to the Installation Instruction Sheet of each part.
Separation tube
B
Horizontal
A
Horizontal line
± 15°
GOOD
A : Outdoor unit or Refrigerant branch kit
B : Indoor unit or Refrigerant branch kit
*5
Header
3-6 Branches 3-8 Branches
UTR-H0906L UTR-H0908L
UTR-H1806L UTR-H1808L
Protection method
Pinch pipes
Pinch or tape pipes
Pinch or tape pipes
Fig.
Pressure regulating valve
Cap
Nitrogen gas
Brazing area
A
B
Vertical
or
B
A
PROHIBITED
Header
Gas pipe
Horizontal line
Outdoor
C
unit side
Liquid pipe
Horizontal line
Outdoor
D
unit side
GOOD
H = 0 to 10 mm
1
(α1: 0° to 1°)
β1: -10° to 10°
H = 0 to 10 mm
2
(α2: 0° to 1°)
β2: -10° to 10°
PROHIBITED
CAUTION
Do not connect a separation tube after a header.
Leave the distance 0.5 m or more for straight part to branch tube and
header.
0.5 m or more
Main pipe
To indoor unit
0.5 m or more
Main pipe
To indoor unit
0.5 m or more
Separation tube
Header
0.5 m or more
To indoor unit
5. 3.

Piping method

5. 3. 1. Opening the knockout hole
CAUTION
Be careful to prevent panel deformation or damaged while opening the knockout
hole.
To prevent cutting of the wiring after the knockout hole was opened, remove the
burrs along the edge.
In addition, to prevent rusting, painting the edge with rust preventive paint is recom-
mended.
The piping can be connected from 2 directions; the front or the bottom.
(Knockout holes are provided so that the piping can be connected from 2 different
directions.)
Use the front knockout hole, as required.
Fig. A Knockout position
1 Horizontal
line
VIEW C
1
H
1
Vertical line
2
H
2
2
VIEW D
PROHIBITED
Separation tube
To indoor
unit
or
Header
To indoor unit
To indoor
unit
or
En-8