Fujitsu Airstage J-II Series Design & Technical Manual page 576

2. PIPING DESIGN
2-1. IMPORTANT ITEMS WHEN USING REFRIGERANT R410A
R410A operates at higher pressure and has less solubility with mineral oil than
traditional R22 refrigerant. Therefore, the lubricant and a part of pipe material are different.
Some special tools are necessary.
„ REFRIGERANT PIPING MATERIAL AND WALL THICKNESS
„
It is necessary to use seamless copper tubes for refrigerant use.
Thickness of tubes are shown in table below.
Endurance pressure of the pipe must be 609 psi (4.2 MPa).
Nominal Diameter (in)
Outside Diameter (mm)
Material
Wall Thickness *2 (mm)
*1: Allowable tensile stress ≥ 33 (N/mm
*2: Endurance pressure of the pipe must be 609 psi (4.2 MPa).
Select the pipe size in accordance with regional standard.
„ LUBRICANT
„
Refrigerant R410A (Mixed refrigerant)
Lubricant
„ TOOLS
„
R410A work requires a number of special tools. Since the tools (with * symbol) for R22 work
cannot be used for R410A, prepare them beforehand.
Tool name
Pipe cutter
Flaring tool *
Torque wrench *
Expander
Pipe bender
Nitrogen gas
Welder
Gauge manifold *
Charging hose *
Vacuum pump (with adaptor) *
Electronic scale for refrigerant charging
Gas leak tester *
*: Refer to a service manual for details.
1/4" 3/8" 1/2"
6.35 9.52 12.70
JIS H3300 C1220T-O or equivalent *1
0.8 0.8 0.8
2
)
Synthetic oil
Pipe cutting
Pipe flaring work
Flare nut connection
Expansion at pipe connection
Pipe bending work
Pipe interior oxidation prevention
Pipe brazing
Vacuum evacuation and refrigerant
charging Operation check
Gas leakage test
- (06 - 12) -
5/8" 3/4"
15.88 19.05
1.0 1.2
Process and application
Refrigerant piping work
Air tightness test
Air tightness test ~
Refrigerant additional charging
Vacuum drying
Refrigerant additional charging