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6-8. Piping Materials and Sizes

nTwin system

Use copper tube of Copper and copper alloy seamless pipes and tubes, with 40mg/10m or less in the
amount of oil stuck on inner walls of pipe and 0.8mm in pipe wall thickness for diameters for diameters 6.4,
9.5 and 12.7mm and 1.0mm, for diameter 15.9mm. Never use pipes of thin wall thickness such as 0.7mm.
In parentheres ( ) are wall thickness

nTriple system

Use copper tube of Copper and copper alloy seamless pipes and tubes, with 40 mg/10 m or less in the
amount of oil stuck on inner walls of pipe and 0.8 mm in pipe wall thickness for diameters 6.4, 9.5 and
12.7 mm and 1.0 mm, for diameter 15.9 mm. Never use pipes of thin wall thickness such as 0.7 mm.
<Between outdoor unit and distributor> [Unit: mm]
( ): Pipe wall thickness
<Between distributor and indoor unit> [Unit: mm]
( ): Pipe wall thickness
Pipe side
Gas side
Liquid side
Main pipe
Branch pipe
Main pipe
Branch pipe
Ø15.9 (1.0)
Ø12.7 (0.8)
Ø9.5 (0.8)
Ø6.4 (0.8)
Outdoor unit
Main pipe Gas side
Liquid side
Ø15.9 (1.0)
Ø9.5 (0.8)
Indoor unit
Branch pipe Gas side
Liquid side
SM56 type
Ø12.7 (0.8)
Ø6.4 (0.8)