SiEN34-705
Heat Pump 60Hz (RXYQ5~54P)
Installation Manual
273
2.6 Refrigerant Piping
Note:
!
All field piping must be installed by a licensed refrigeration technician and must comply with
relevant local and national regulations.
!
After piping work is complete, do not under any circumstances open the shutoff valve until
“2-7. Field Wiring” and “2-10. Checking of Device and Installation Conditions” are complete.
!
Do not use flux when brazing the refrigerant piping. Use the phosphor copper brazing filler
metal (BCuP-2: JIS Z 3264/B-Cu93P-710/795: ISO 3677) which does not require flux.
(Flux has extremely harmful influence on refrigerant piping systems. For instance, if the
chlorine based flux is used, it will cause pipe corrosion or, in particular, if the flux contains
fluorine, it will damage the refrigerant oil.)
2.6.1 Selection of Piping Material and Refrigerant Branching Kit
!
Use only pipes which are clean inside and outside and which do not accumulate harmful
sulfur, oxidants, dirt, cutting oils, moisture, or other contamination. (Foreign materials inside
pipes including oils for fabrication must be 30mg/10m or less.)
!
Use the following items for the refrigerant piping.
Material:
Jointless phosphor-deoxidized copper pipe
Size:
See “2-6-5 Example of connection” to determine the correct size.
Thickness:
Select a thickness for the refrigerant piping which complies with national and
local laws.
For R-410A, the design pressure is 4.0 MPa (40-bar).
The minimum thickness of piping according to Japan’s High-Pressure Gas Safety Law (as of
January 2003) is shown below.
Temper grade (O type, 1/2H type) in the table indicate the material types specified in JIS H
3300.
!
For piping work, follow the maximum tolerated length, difference in height, and length after a
branch indicated in the
“2-6-5 Example of connection”
.
!
A refrigerant branching kit (sold separately) is needed for piping branches and connection of
piping between outdoor unit (in case of multi system).
Use only separately sold items selected specifically according to the refrigerant branch kit
selection in the
“2-6-5 Example of connection”
.
2.6.2 Protection Against Contamination when Installing Pipes
Protect the piping to prevent moisture, dirt, dust, etc. from entering the piping.
Note:
Exercise special caution to prevent dirt or dust when passing piping through holes in walls and
when passing pipe edges to the exterior.
(unit: mm)
Temper grade
O type
outer diameter
φ
6.4
φ
9.5
φ
12.7
φ
15.9
smallest thickness
0.80
0.80
0.80
0.99
(unit: mm)
Temper grade
1/2H type
outer diameter
φ
19.1
φ
22.2
φ
25.4
φ
28.6
φ
31.8
φ
34.9
φ
38.1
φ
41.3
smallest thickness
0.80
0.80
0.88
0.99
1.10
1.21
1.32
1.43
Place
Installation period
Protection method
Outdoor
More than a month
Pinch the pipe
Less than a month
Pinch or tape the pipe
Indoor
Regardless of the period
