Pipe Installation; Brazing; Indoor Unit Pipe Connections; Opening The Knockout Hole - Fujitsu AirStage AJY040LELAH Installation Manual

5. PIPE INSTALLATION

5.1. Brazing

If air or another type of refrigerant enters the
refrigeration cycle, the internal pressure 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 (= pressure
felt suffi ciently on the back of your hand)
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 compressor
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

For details, refer to the Installation Instruction Sheet of each part.
Separation tube
A
:
Outdoor unit or Refrigerant
branch kit
A
B
:
Indoor unit or Refrigerant
branch kit ± 15°
PROHIBITED
Header
Horizontal line
Gas pipe
C
Outdoor
GOOD
unit side
Horizontal line
Liquid pipe
D
Outdoor
unit side
GOOD
PROHIBITED
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
CAUTION
Pressure regulating valve
Cap
Nitrogen gas
Brazing area
CAUTION
Horizontal Vertical
A
B
or
Horizontal line
B
GOOD GOOD
Horizontal line
β
1
H = 0 to 10 mm
1
(α : 0° to 1°)
1
α
C
View β : -10° to 10°
1
1
H
1
Vertical line
H = 0 to 10 mm
2
α
(α : 0° to 1°)
2 2
β
H
2
β : -10° to 10°
2
2
View D
CAUTION
Separation tube
To indoor
unit
or
Header
To indoor unit
0.5 m or more

5.3. Opening the knockout hole

Be careful not to deform or scratch the panel while opening the knockout holes.
To protect the piping insulation after opening a knockout hole, remove any burrs from
the edge of the hole. It is recommended to apply rust prevention paint to the edge of the
hole.
• Pipes can be connected from 4 directions, front, lateral side, rear side and bottom.
(Fig. A)
• When connecting at the bottom, remove the service panel and piping cover on the front
of the outdoor unit, and open the knockout hole provided at the bottom corner of the
piping outlet.
• It can be installed as shown on "Fig. B" cutting out the 2 slits as indicated on "Fig. C".
(When cutting slits, use a steel saw.)
Fig. A
B
Service
panel
A
Fig. B
Slit
Front connection
0.5 m or more
Separation tube
To indoor
unit
or
Header
To indoor unit
CAUTION
Fig. C
Slit
Lateral connection Bottom connection
Bottom
connection
Rear connection
En-6