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15
Digital Inverter
Installation Manual
EN-29
EN-30
H
A
Nitrogen gas pressure 0.5 MPa
Existing pipes: Cannot be used.
• Use new pipes.
Connect the indoor/outdoor units to the existing pipe.
• Use a flare nut attached to the main unit for the
indoor/outdoor units. (Do not use the flare nut of the
existing pipe.)
• Re-machine the flare machining size to size for R410A.
•
After the existing air conditioner is operated in cooling
mode for approx. 30 minutes or longer,* recover the
refrigerant.
•
For cleaning the pipes and recovering oil
•
Refrigerant recovery: Refrigerant recovery equipment
• (Airtight test), Vacuum dry, Refrigerant charge, Gas leak
check
• Remove the existing air conditioner from the piping and
carry out flushing (nitrogen pressure 0.5 MPa) to remove
any remains inside of the pipe.
Was largely discolored oil or a large quantity
of remains discharged? (When the oil
deteriorates, the color of the oil changes to a
muddy or black color.)
(If there is discharge of remains, it is judged that a
large quantity of remains are present.)
Piping necessary to change the flare nut/
machining size due to pipe compression
Clean the pipes or use new pipes.
In case of twin pipes, also be sure to flush the
branching pipe.
Note]
Test run
1) Flare nut width: H
2) Flare machining size: A
(mm)
(mm)
Becomes a little larger for R410A
For R410A
For R22
Copper pipe
outer
diameter
For R410A
For R22
Same as above
Same as
above
Do not apply refrigerator oil to the flare surface.
Ø6.4
Ø9.5
Ø12.7
Ø15.9
Ø19.1
17
22
26
29
36
24
27
Ø6.4
Ø9.5
Ø12.7
Ø15.9
Ø19.1
9.1
13.2
16.6
19.7
24.0
9.0
13.0
16.2
19.4
23.3
Copper pipe
outer
diameter
NO
YES
YES
YES
NO
NO
Are there scratches or dents on the existing pipes?
Is it possible to operate the existing air conditioner?
