Mitsubishi Electric PUHY-HP120TNU-A, Service Handbook

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[1-2 Handling and Characteristics of Piping Materials, Refrigerant, and Refrigerant Oil ]
HWE18240_GB
chapter 1 -
3
1 Check Before Servicing
1-2 Handling and Characteristics of Piping Materials,
Refrigerant, and Refrigerant Oil
1-2-1 Piping Materials
1. Copper pipe materials
Œ
The distinction between Annealed and Drawn is made based on the strength of the pipes themselves.
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Annealed can easily be bent with hands.
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Drawn are considerably stronger than Annealed at the same thickness.
2. Types of copper pipes
3. Piping materials/Radial thickness
Select piping materials that meet the requirements set forth in ASTM B280.
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 (R410A).
5. Flare processing
Select piping materials that meet the requirements set forth in ASTM.
6. Flare nut
Select piping materials that meet the requirements set forth in ASTM.
Annealed Soft copper pipes (annealed copper pipes). They can easily be bent with hands.
Drawn Hard copper pipes (straight pipes). They are stronger than the Annealed at the same
radial thickness.
Maximum working pressure Refrigerant type
3.45 MPa [500psi] R22, R407C etc.
4.30 MPa [624psi] R410A etc.
Do not use the existing piping!