3 Piping work and refrigerant charge
Refrigerant pipe selection
SMGB0099 rev.0 - 12/2016
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3.1  Refrigerant pipe selection
3.1.1  Refrigerant pipe selection
? NOTE
Consult the corresponding Technical Catalogue for outdoor units from the UTOPIA or SET FREE Series.
 
Pipe size selection
Select the pipe size in line with the following instructions:
1  Between the outdoor unit and the branch pipe (multi-kit): select the same pipe connection size as for the outdoor unit.
2  Between the branch pipe (multi-kit) and the indoor unit: select the same pipe connection size as for the indoor unit.
! CAUTION
•  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 difculties 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.
 
Multi-kit or distributor selection
? NOTE
•  Pipe connection sizes on outdoor units, indoor units and the multi-kit 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 are adapter (accessory) to the indoor pipe connection.