Screw Compressor Central Chiller
Chapter 3: Installation
21
Water Connection Sizing Considerations
Note:
x
Run all external chilled water connections with adequate size to the
process.
x
Provide the largest possible openings and passages for the flow of
chilled water through platens, dies, molds, or other pieces of
equipment.
x
Minimum external pressure drop is
critical
for proper operation.
Galvanic Corrosion Considerations
Water circuit piping components are primarily ferrous (iron) and react electro-chemically
with non-ferrous metallic materials such as copper. Some water has dissolved minerals that
will greatly accelerate the reaction between dissimilar metals.
Use PVC or ferrous piping to minimize galvanic action. If piping must be copper, use
dielectric unions at the chiller.
Water Treatment Considerations
Water treatment is important in any piping system. In some locations, raw water may be used
in the system without problem; in other locations, it will result in large deposits of scale and
corrosion.
We offer a complete line of water treatment equipment. Contact your sales representative for
water testing and treatment options.
Making Water-Cooled Condenser Connections
Screw compressor water-cooled chilling stations use city or tower water as a cooling
medium. All external condenser supply, discharge piping and connections should be of
adequate size. Water regulating valves are not required on the Screw Compressor Chiller if
the tower water does not fall below 65°F (18ºC). Water flow must be adjusted based upon
the pressure drop in the following table on the next page.
Two connections are made to each unit:
Condenser Water In
The optional condenser water manifold allows one-point connection of
TO TOWER
(drain)
and
FROM TOWER
(city water) piping. Sch. 40 steel include butterfly valves for each
condenser.
The city or tower water supply inlet is located at the side or rear of the chiller.
x
Water pressure
t
25 psi (
t
172.4 kPa/
t
1.72 bars)
x
Water temperature
d
85°F (
d
29ºC)
