1
M = E + W + B
W + B
E + W + B
N =
N - 1
1
B =
x E - W
N - 1
N
M =
x E
1
overflow
(Overflow at cooling tower via
manual valve)
2
Constant blow-down
(Constant blow-down via
solenoid valve)
3
Pressure switch and solenoid
valve
(Blow-down via solenoid valve
at pressure switch)
4
Conductivity meter and/or pH
meter
(Blow-down by conductivity or
pH)
4.4 - exhibit Le (cont.)
4.4.5 - Cooling water blow-down method
Prevent concentration and replace cooling water by blow-down.
Calculate the blow-down volume as follows.
N:
Concentration factor (N = 3 is normal condition)
M:
Volume of make-up water
E:
Evaporation loss = 860 x 2.43 (exhaust heat factor) divided by 575 (latent heat of water at 40°C) = 3.63 l/h/kW
W:
Splash loss (0.2% of circulation water volume)
B:
Blow-down volume
P
P
P
P
Chiller
Manual valve
Make-up water
overflow
Make-up water
blow-down
adjustment valve
Chiller
Chiller
Chiller
Higher than cooling tower
water level
Make-up water
Make-up water
Solenoid
valve
Solenoid
valve
overflow
Sensor
Control panel
Pressure
switch
Cooling water flow rate = 230 l/h/kW
(chiller cooling capacity)
E = 3.63 l/h/kW
N = 3
W = 0.46 l/h
B =
B = 1.36 l/h/kW
3 - 1
1
x 3.63 - 0.46
example
Summary of Contents for Carrier 16LJ Series
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