Samsung AM***XMDCH Series Installation Manual page 13

Selecting refrigerant pipe
Temper grade and minimum thickness of the refrigerant pipe
Outer diameter [mm (inch)]
Ø6.35 (1/4)
Ø9.52 (3/8)
Ø12.70 (1/2)
Ø15.88 (5/8)
Ø19.05 (3/4)
Ø22.22 (7/8)
Make sure to use C1220T-1/2H (Semi-hard) or C1220T-H pipe for more than Ø19.05mm (3/4 inch).
In case of using C1220T-O (Soft) pipe for Ø19.05mm (3/4 inch), pipe may be broken, which can result in an injury.
Pipe installation between an outdoor unit and the first Y-joint
Outdoor unit capacity
[HP(Ton)]
7(5)
Install the refrigerant pipe according to main pipe size of each outdoor unit capacity.
When the pipe length between an outdoor unit and the farthest indoor unit including elbow exceeds 90m (295ft), the
gas pipe size should be upgraded one step among the main pipes from the outdoor unit to the first Y-joint. (The liquid
pipe size will be maintained.)
If the capacity of the outdoor unit can decline due to the pipe length, upgrade the pipe size one step (gas pipe).
Main pipe size up
Pipe installation between Y-joints
Indoor unit total capacity
[kW (Btu/h)]
X ≤ 15.0 (51000)
15.0 (51000) < X ≤ 23.2 (79000)
Minimum thickness [mm (inch)]
Liquid pipe [mm (inch)]
Ø9.52 (3/8)
First Y-joint
Liquid pipe [mm (inch)]
Ø9.52 (3/8)
0.7 (0.028)
0.7 (0.028)
0.8 (0.031)
1.0 (0.039)
0.9 (0.035)
0.9 (0.035)
Gas pipe [mm (inch)]
Ø19.05 (3/4)
Temper grade
Annealed
Drawn
One step upgraded pipe
[mm (inch)]
Ø22.22 (7/8)
Gas pipe [mm (inch)]
Ø15.88 (5/8)
Ø19.05 (3/4)
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