Pipe Connection; Multiple Connections - Fujitsu AirStage AJ 072GALDH Series Installation Manual

5.4. Pipe connection

Do not use mineral oil on a flared part. Prevent mineral oil from getting into the system
as this would reduce the lifetime of the units.
While brazing the pipes, be sure to blow dry nitrogen gas through them.
The maximum lengths of this product are shown in the table. If the units are further
apart than this, correct operation cannot be guaranteed.
5.4.1 Bending pipes
To prevent breaking of the pipe, avoid sharp bends. Bend the pipe with a radius of
curvature of 100 mm or more.
If the pipe is bent repeatedly at the same place, it will break.
• If pipes are shaped by hand, be careful not to collapse them.
• Do not bend the pipes at an angle of more than 90°.
• When pipes are repeatedly bent or stretched, the material will harden, making it difficult
to bend or stretch them anymore.
• Do not bend or stretch the pipes more than 3 times.
5.4.2 Removing the pinch pipe
Remove the pinch pipe only when the internal gas is completely drained as shown on
the below instructions.
If gas still remains inside, the piping may crack if you melt the brazing filler metal of the
junction area with a burner.
Before connecting the piping, remove the pinch pipe in accordance with the following
instructions:
(1) Verify that the liquid (2) Cut the end of the
side, suction gas side liquid side, suction gas
and discharge gas side and discharge gas
side 3-way valves are side pinch pipe and
closed. vent the gas inside the
pinch pipe.
3-way
valves
5.4.3 Pipe connection
Seal the pipe route hole with putty (Locally purchased) such that there are no gaps.
Small insects or animals that are trapped in the outdoor unit may cause a short circuit in the
electrical component box.
To prevent pipe damage; do not make sharp bends.
Bend the pipe at a radius of 70 mm or greater.
Do not bent pipe many times at same part to prevent break.
After completing all the pipe connection by brazing, perform the indoor unit pipe
connection with a flare joint.
When removing the pinch pipe or brazing the joint pipe, carry out the work while cooling
down the 3-way valve sufficiently.
• Braze the joint pipe onto the 3-way valves at the liquid, suction gas and discharge gas
side.
Install the joint pipe appropriately so that it can be connected easily with the main pipe.
• Braze the joint pipe at the liquid, suction gas and discharge gas side with the main pipe.
* Be sure to supply nitrogen when brazing.
En-9
CAUTION
CAUTION
WARNING
(3) After all the gas is
vented, melt the
brazing filler metal on
connecting part using
a torch and remove
the pinch pipe.
End of pinch pipe
CAUTION
Fig. A
Joint pipe
(Locally purchased)
Liquid pipe
(Locally purchased)
Fig. B
Joint pipe
(Locally purchased)

5.5. Multiple connections

• When connecting multiple (maximum 3) units, be sure to install the unit with the
largest capacity nearest to the indoor unit.
For example: AJ*108GALDH (Outdoor Unit1) + AJ*090GALDH (Outdoor Unit2) +
AJ*072GALDH (Outdoor Unit3)
• When connecting multiple units, set the unit with the largest capacity as the primary unit,
and the rest as the subordinate units. (Refer to "7. FIELD SETTING")
• When connecting multiple units, use the optional outdoor unit branch kit.
Outdoor unit
branch kit
(Optional)
To indoor unit
(To main pipe)
To outdoor unit
To outdoor unit
Joint pipe D
(Accessory)
Joint pipe B
(Accessory)
Knockout hole
Suction gas pipe
(Locally purchased)
Discharge gas pipe
(Locally purchased)
To RB unit or indoor unit
Joint pipe C
(Accessory or locally
purchased) (*1)
Joint pipe A
(Accessory or locally
purchased) (*1)
Knockout hole
*1: Locally purchased and accessory
depend on the model, so for details,
refer "2.3. Accessories".
CAUTION
Outdoor Capacity
2 Units: Unit 1 ≥ Unit 2
3 Units: Unit 1 ≥ Unit 2 ≥ Unit 3
Joint pipe
(Accessory)
Liquid pipe
(Locally
purchased)
Discharge gas pipe
(Locally purchased)
Suction gas pipe
(Locally purchased)