Cautions For Service; Additional Refrigerant Charge; Service Tools; Thickness Of Pipes - Mitsubishi Electric Mr.SLIM PU-P71VHA Service Manual

[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.)

[3] Service tools

Use the below service tools as exclusive tools for R410A refrigerant.
No.
1
Gauge manifold
2
Charge hose
3
Electronic scale
4
Gas leak detector
5
Adaptor for reverse flow check
6
Refrigerant charge base
7
Refrigerant cylinder
8
Refrigerant recovery equipment
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.

1Thickness 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.)
Diagram below: Piping diameter and thickness
Nominal Outside
diameter (mm)
dimensions
1/4" 6.35
3/8" 9.52
1/2" 12.70
5/8" 15.88
3/4" 19.05
OC379F
Gravimeter
Tool name
Thickness (mm)
R410A
0.8
0.8
0.8
1.0
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· Only for R410A
· Use the existing fitting specifications . (UNF1/2)
· Use high-tension side pressure of 5.3MPa·G or over.
· Only for R410A
· Use pressure performance of 5.09MPa·G or over.
· Use the detector for R134a, R407C or R410A.
· Attach on vacuum pump.
· Only for R410A · Top of cylinder (Pink)
· Cylinder with syphon
R22
0.8
0.8
0.8
1.0
1.0
6
Unit
Specifications
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