Refrigerant Piping Size And Multikit/Distributor Selection - Hitachi RAS-2-HVNP Service Manual

3. Piping work and refrigerant charge
3.3.5 Refrigerant piping size and multikit/distributor selection
C A U T I O N
• Do not use refrigerant pipe sizes other than those indicated in this Technical Catalogue. The diameter of the
refrigerant pipes depends directly on the outdoor unit capacity.
• If larger diameter gas refrigerant pipes are used, the circuit lubrication oil tends to separate from the gas ca-
rrying it. The compressor will be seriously damaged due to a lack of lubrication.
• If smaller diameter gas 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.
Select the piping connection sizes according to the following procedures
• Between outdoor unit and branch pipe: Select the same pipe connection size as the pipe size of the outdoor unit.
• Between branch pipe and indoor unit: Select the same pipe connection size as the pipe size of the indoor unit.
1 indoor unit system
2 indoor units system
67
Outdoor Unit HP
2 / 2.5
3 - 6
8
10 / 12
Outdoor Unit HP
2 / 2.5
3 / 4
5 / 6
8
10 / 12
Indoor Unit capacity
≤ 1.5 HP
1.8 / 2.0 HP
> 2.3 HP
SMGB0079 rev.0 - 01/2013
(mm)
Pipe Size (L)
Gas Liquid
Ø12.70 Ø6.35
Ø15.88 Ø9.52
Ø25.40 Ø9.52
Ø25.40 Ø12.70
(mm)
Pipe Size (A) IVX Premium Series
Gas Liquid
Ø12.70 Ø6.35
Ø15.88 Ø9.52
Ø15.88 Ø9.52
Ø25.40 Ø9.52
Ø25.40 Ø12.70
(mm)
Pipe Size (B, C)
Gas Liquid
Ø12.70 Ø6.35
Ø15.88 Ø6.35
Ø15.88 Ø9.52
Multi-kit
IVX Standard Series
TW-22AN TE-03N1
3HP: TE-03N1
TW-52AN
4HP: TE-04N1
TW-52AN TE-56N1
TW-102AN TE-08N
TW-102AN TE-10N
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