Screw Compressor Central Chiller
Chapter 3: Installation
25
Liquid Line Sizing
The liquid line should be sized as small as possible while maintaining acceptable pressure
drop to minimize the refrigerant charge. Liquid line risers should not exceed 15 feet from the
base of the air-cooled condenser. Horizontal runs do not require a pitch. Insulation is
recommended to prevent heat losses/gains and condensation due to unusual ambient
conditions. Install a liquid line-charging valve to facilitate refrigerant charging. See Figure 3
for liquid line sizing information. See Figure 6 for charge determination.
Figure 3: Liquid Line Sizing
30 – 65°F Leaving Water Temperature
Liquid Line Size (O.D.”)
Equiv. Ft.
35 hp
40 hp
50 hp
60 hp
70 hp
80 hp
90 hp
110 hp
25
7/8
7/8
1 1/8
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
50
1 1/8
1 1/8
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
1 3/8
75
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
100
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
125
1 1/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
2 1/8
150
1 3/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
2 1/8
175
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
2 1/8
2 1/8
200
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
225
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
250
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
275
1 3/8
1 5/8
1 5/8
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
300
1 3/8
1 5/8
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
2 1/8
