Pipe Design; Important Items When Using Refrigerant (R410A) - Fujitsu AU*G36LRLA Design & Technical Manual

1.

PIPE DESIGN

1-1.

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. The design pressure is 4.2 MPa.
Nominal Diameter
Outside Diameter
Material
Wall Thickness *2
*1: Allowable tensile stress ≥ 33 (N/mm
*2: Design pressure 4.2MPa
Please select the pipe size in accordance with local rules.
LUBRICANT
„ „
Refrigerant
Lubricant
TOOLS
„ „
R410A work requires a number of special tools. Since the tools (with *3 symbol) for R22 work
cannot be used for R410A, prepare them beforehand.
Tool name
Pipe cutter
Flaring tool *3
Torque wrench *3
Expander
Pipe bender
Nitrogen gas
Welder
Gauge manifold *3
Charging hose *3
Vacuum pump (with adaptor) *3
Electronic scale for refrigerant charging
Gas leak tester *3
*3: Please refer to a service manual for details.
(in) 1/4" 3/8"
(mm) 6.35 9.52
JIS H3300 C1220T-O or equivalent *1
(mm) 0.8 0.8
2
)
R410A (Mixed refrigerant)
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
1/2"
12.70
0.8
Synthetic oil
Process and application
- (05-01) -
5/8" 3/4"
15.88 19.05
1.0 1.2
Refrigerant piping work
Air tightness test
Air tightness test ~
Refrigerant additional charging
Vacuum drying
Refrigerant additional charging