Hitachi RAS-4-HNCE - Refrigerant Piping Size and Multikit;Distributor Selection

3. Piping work and refrigerant charge
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SMGB0079 rev.0 - 01/2013
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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difculties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
(mm)
Outdoor Unit HP
Pipe Size (L)
Gas Liquid
2 / 2.5 Ø12.70 Ø6.35
3 - 6 Ø15.88 Ø9.52
8 Ø25.40 Ø9.52
10 / 12 Ø25.40 Ø12.70
2 indoor units system
(mm) Multi-kit
Outdoor Unit HP
Pipe Size (A) IVX Premium Series IVX Standard Series
Gas Liquid
2 / 2.5 Ø12.70 Ø6.35
TW-22AN TE-03N1
3 / 4 Ø15.88 Ø9.52
TW-52AN
3HP: TE-03N1
4HP: TE-04N1
5 / 6 Ø15.88 Ø9.52
TW-52AN TE-56N1
8 Ø25.40 Ø9.52
TW-102AN TE-08N
10 / 12 Ø25.40 Ø12.70
TW-102AN TE-10N
(mm)
Indoor Unit capacity
Pipe Size (B, C)
Gas Liquid
≤ 1.5 HP Ø12.70 Ø6.35
1.8 / 2.0 HP Ø15.88 Ø6.35
> 2.3 HP Ø15.88 Ø9.52