Refrigerant Pipe Selection - Hitachi RCI-1.0FSN3 Service Manual

3 Piping work and
refrigerant charge

3.1 Refrigerant pipe selection

3.1.1 Refrigerant pipe selection
N O T E
Consult the corresponding Technical Catalogue for outdoor units from the UTOPIA or SET FREE Series.
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Pipe size selection
Select the pipe size in line with the following instructions:
1 Between the outdoor unit and the branch pipe (multikit): select the same pipe connection size as for the outdoor unit.
2 Between the branch pipe (multikit) and the indoor unit: select the same pipe connection size as for the indoor unit.
C A U T I O N
• Do not use refrigerant pipe sizes other than those indicated in the corresponding Technical Catalogue for
outdoor units. The diameter of the refrigerant pipes depends directly on the power of the outdoor unit.
• If larger diameter refrigerant pipes are used, the circuit lubrication oil tends to separate from the gas carrying
it. The compressor will be seriously damaged due to a lack of lubrication.
• If smaller diameter refrigerant pipes are used, the gas or liquid refrigerant will have serious difficulties in
circulating. System performance will be affected. The compressor will run under more severe conditions than
foreseen and will be damaged in a short space of time.
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Multikit or distributor selection
N O T E
Pipe connection sizes on outdoor units, indoor units and the multikit or distributor vary depending on the
•
system. Consult the Service Manual for the UTOPIA or SET FREE Series.
• The sizes of the indoor and outdoor units are different. Adjust the flare adapter (accessory) to the indoor pipe
connection.
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SMGB0077 rev.0 - 01/2013