6
Gravimeter
Unit
[3] Service tools
Use the below service tools as exclusive tools for R410A refrigerant.
Cautions for refrigerant piping work
New refrigerant R410A is adopted for replacement inverter series. Although the refrigerant piping work for R410A is same
as for R22, exclusive tools are necessary so as not to mix with different kind of refrigerant. Furthermore as the working
pressure of R410A is 1.6 times higher than that of R22, their sizes of flared sections and flare nuts are different.
1
Thickness of pipes
Because the working pressure of R410A is higher compared to R22, be sure to use refrigerant piping with thickness
shown below. (Never use pipes of 0.7mm or below.)
1/4”
3/8”
1/2”
5/8”
3/4”
6.35
9.52
12.70
15.88
19.05
0.8
0.8
0.8
1.0
—
0.8
0.8
0.8
1.0
1.0
Nominal
dimensions
Diagram below: Piping diameter and thickness
Outside
diameter (mm)
Thickness (mm)
R410A
R22
No.
Tool name
Specifications
1
Gauge manifold
· Only for R410A
· Use the existing fitting specifications. (UNF1/2)
· Use high-tension side pressure of 5.3MPa·G or over.
2
Charge hose
· Only for R410A
· Use pressure performance of 5.09MPa·G or over.
3
Electronic scale
—
4
Gas leak detector
· Use the detector for R134a, R407C or R410A.
5
Adaptor for reverse flow check
· Attach on vacuum pump.
6
Refrigerant charge base
—
7
Refrigerant cylinder
· Only for R410A · Top of cylinder (Pink)
· Cylinder with syphon
8
Refrigerant recovery equipment
—
[1] Cautions for service
(1) Perform service after collecting the refrigerant left in unit completely.
(2) Do not release refrigerant in the air.
(3) After completing service, charge the cycle with specified amount of refrigerant.
(4) When performing service, install a filter drier simultaneously.
Be sure to use a filter drier for new refrigerant.
[2] Additional refrigerant charge
When charging directly from cylinder
· Check that cylinder for R410A on the market is syphon type.
· Charging should be performed with the cylinder of syphon stood vertically. (Refrigerant is charged from liquid phase.)
OC379F
