Mitsubishi Electric PUHY-P250YNW-A Service Handbook page 15

[1-2 Handling and Characteristics of Piping Materials, Refrigerant, and Refrigerant Oil ]
4. Thickness and refrigerant type indicated on the piping materials
Ask the pipe manufacturer for the symbols indicated on the piping material for new refrigerant.
5. Flare processing (O-material (Annealed) and OL-material only)
The flare processing dimensions for the pipes that are used in the R410A system are larger than those in the R22 system.
Flare processing dimensions (mm[in])
Pipe size (mm[in])
ø6.35 [1/4"]
ø9.52 [3/8"]
ø12.7 [1/2"]
ø15.88 [5/8"]
ø19.05 [3/4"]
If a clutch-type flare tool is used to flare the pipes in the system using R410A, the length of the pipes must be between 1.0
and 1.5 mm. For margin adjustment, a copper pipe gauge is necessary.
6. Flare nut
The flare nut type has been changed to increase the strength. The size of some of the flare nuts have also been changed.
Flare nut dimensions (mm[in])
Pipe size (mm[in])
ø6.35 [1/4"]
ø9.52 [3/8"]
ø12.7 [1/2"]
ø15.88 [5/8"]
ø19.05 [3/4"]
The figures in the radial thickness column are based on the Japanese standards and provided only as a reference. Use pipes
that meet the local standards.
4 -
chapter 1
A dimension (mm)
R410A R22, R407C
9.1 9.0
13.2 13.0
16.6 16.2
19.7 19.4
24.0 23.3
B dimension (mm)
R410A R22, R407C
17.0 17.0
22.0 22.0
26.0 24.0
29.0 27.0
36.0 36.0
Dimension B
BS_01_C