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3
Digital Inverter
Installation Manual
EN-5
EN-6
3
INSTALLATION OF NEW REFRIGERANT AIR
CONDITIONER
CAUTION
New Refrigerant Air Conditioner Installation
• THIS AIR CONDITIONER ADOPTS THE NEW HFC REFRIGERANT (R410A) WHICH DOES NOT DESTROY
OZONE LAYER.
R410A refrigerant is apt to be affected by impurities such as water, oxidizing membrane, and oils because the working
pressure of R410A refrigerant is approx. 1.6 times as that of refrigerant R22. Accompanied with the adoption of the
new refrigerant, the refrigerant oil has also been changed. Therefore, during installation work, be sure that water, dust,
former refrigerant, or refrigerant oil does not enter the new type refrigerant R410A air conditioner cycle.
To prevent mixing of refrigerant or refrigerant oil, the sizes of connecting sections of charging port on main unit and
installation tools are different from those of the conventional refrigerant units. Accordingly, special tools are required
for the new refrigerant (R410A) units. For connecting pipes, use new and clean piping materials with high pressure
fittings made for R410A only, so that water and/or dust does not enter.
Required Tools/Equipment and Precautions for Use
Prepare the tools and equipment listed in the following table before starting the installation work.
Newly prepared tools and equipment must be used exclusively.
Legend
: Prepared newly (Use for R410A only. Do not use for refrigerant R22 or R407C etc.)
: Conventional tools/equipment are available
Tools/equipment
Use
How to use tools/equipment
Gauge manifold
Vacuuming/charging refrigerant
and operation check
Prepared newly for R410A only
Charging hose
Prepared newly for R410A only
Charging cylinder
Can not be used
Unusable (Use the refrigerant charging measure
instead.)
Gas leak detector
Gas leak check
Prepared newly
Vacuum pump
Vacuum drying
Unusable
Vacuum pump with backflow
prevention function
Vacuum drying
R22 (Conventional tools)
Refrigerant Piping
New refrigerant (R410A)
When using the conventional piping
• When using the conventional piping with no indication of applicable refrigerant types, be sure to use it with a wall
thickness of 0.8 mm for Ø12.7 mm, with a wall thickness of 1.2 mm for Ø19.1 mm, and with a wall thickness of 1.0
mm for Ø28.6 mm (half hard). Do not use the conventional piping with a wall thickness less than these thicknesses
due to insufficient pressure capacity.
When using general copper pipes
• Use general copper pipes with a wall thickness of 0.8 mm for Ø12.7 mm, with a wall thickness of 1.2 mm for Ø19.1
mm, and with a wall thickness of 1.0 mm for Ø28.6 mm (half hard).
Do not use any copper pipes with a wall thickness less than these thicknesses.
Flare nuts and flare machining
• The flare nuts and flare machining are different from those for the conventional refrigerant.
Use the flare nuts supplied with the air conditioner or those for R410A.
• Before performing flare machining, carefully read “REFRIGERANT PIPING”.
Flare tool
Flare machining of pipes
Usable if dimensions are adjusted.
Bender
Bending pipes
R22 (Conventional tools)
Refrigerant recovery equipment Refrigerant recovery
For R410A only
Torque wrench
Tightening flare nuts
Exclusive for Ø12.7 mm and Ø19.1 mm
Pipe cutter
Cutting pipes
R22 (Conventional tools)
Welding machine and nitrogen
cylinder
Welding pipes
R22 (Conventional tools)
Refrigerant charging measure
Charging refrigerant
R22 (Conventional tools)
Tools/equipment
Use
How to use tools/equipment