Application:
Both the two-way and three-way valves are suitable for shut-off and flow regulation purposes.
The cost of the two-way valves are cheaper compared with the three-way valves. Thus,
there is a tendency to use the two-way valves during installations.
A typical two-way valve installation:
The problem with the above installation occurs when both the fan coil units are switched off.
he controls of the fan coil unit will also at the same time switch off the solenoid valves, i.e.
FAN COIL UNIT 1
FAN COIL UNIT 2
Mini Chille
2-way solenoid
2-way solenoid
T
there will not be any water flow through the system when the fan coils are not in use.
However, the chiller pump is still running. Therefore, the water pressure built-up in the piping
may cause damage to the water pump or to the valves themselves (valve stem lifting).
Usage of 2-way valves will require additional design considerations:
a. Add a Bypass Line to Relief Pressure
LOAD
∆
P
LOAD
LOAD
Different pressure transmitter to monitor the amount of water used. If
pressure goes higher than preset value, it will open the relief
bypass the water
valve and
Section 3 Page 49
To Next Page
Loading...
