Specifications
81
%!!. Piping Design
1. R410A Piping material
Refrigerant pipe for PFAV shall be made of phosphorus deoxidized copper, and has two types.
• Type-O : Soft copper pipe (annealed copper pipe), can be easily bent with human's hand.
• Type-1/2H pipe : Hard copper pipe (Straight pipe), being stronger than Type-O pipe of the same radical
thickness.
The maximum operation pressure of R410A air conditioner is 4.30 MPa [623psi]. The refrigerant piping
should ensure the safety under the maximum operation pressure. MITSUBISHI ELECTRIC recommends
pipe size as Table 1-1, or You shall follow the local industrial standard. Pipes of radical thickness 0.7mm or
less shall not be used.
Flare
Due to the relative higher operation pressure of R410A compared to R22, the flare connection should follow
dimensions mentioned below so as to achieve enough the air-tightness.
* For pipe sized ø19.05 (3/4") for R410A air conditioner, choice of pipe type is up to you.
* 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.
Size (mm) Size (inch) Radial thickness (mm) Pipe type
ø1/4" 0.8
ø3/8" 0.8
ø1/2" 0.8 Type-O
Type-O
Type-O
Type-O
Type-O
ø5/8"
ø3/4"
ø3/4"
ø7/8" 1.0
1.0
1.0
Type-1/2H or H
Type-1/2H or H
Type-1/2H or H
Type-1/2H or H
Type-1/2H or H
Type-1/2H or H
Type-1/2H or H
ø1" 1.0
ø1-1/8" 1.0
ø1-1/4" 1.1
ø1-3/8" 1.2
1.2
ø41.28 ø1-5/8" 1.4
Radial thickness (mil)
[32]
[32]
[32]
[40]
[40]
[40]
[40]
[40]
[44]
[48]
[48]
[56]
Table 1-1. Copper pipe size and radial thickness for R410A PFAV
ø6.35
ø9.52
ø12.7
ø15.88
ø19.05
ø19.05
ø22.2
ø25.4
ø28.58
ø31.75
ø34.93
Flare pipe Pipe size A (For R410A) Flare nut Pipe size
(mm[in.]) (mm[in.])
B (For R410A)
ø6.35 [1/4"]
ø9.52 [3/8"]
ø12.70 [1/2"]
ø15.88 [5/8"]
ø19.05 [3/4"]
24.0
16.6
19.7
9.1
13.2
ø6.35 [1/4"]
ø9.52 [3/8"]
ø12.70 [1/2"]
ø15.88 [5/8"]
ø19.05 [3/4"]
36.0
17.0
22.0
26.0
29.0
A
B