Water Make-Up Requirements of Cooling Towers
Evaporative cooling towers, like the ADVANTAGE Power Tower® Series, provide cooling by evaporating a small amount of the recirculated process water flow.
- Approximately 1,000 BTU’s are required to evaporate .12 gallons of water. Therefore, every tower ton (15,000 BTU/hr) requires approximately 1.8 gallons of water evaporation, or .03 gpm/ton.
- As water evaporates in a cooling tower system, the water vapor enters the atmosphere while any dissolved solids remain behind, building concentration in the remaining water.
- Most water treatment systems control this concentration by bleeding off the high concentration water, which is made up by fresh city water with a lower solid concentration. The amount of water that is
bled off by the water treatment system is usually less than or equal to the amount of water that evaporates. - Therefore, the maximum normal water makeup for a cooling tower system is .06 gpm / ton, or about 2% of the nominal tower flow rate.
- The following chart specifies the Maximum Water Make Up requirement per model.
Model shown: TC-135G3
The following chart specifies the Maximum Water Make Up requirement per model.
Maximum Evaporation
1.35 GPM
at designed capacity
Nominal Tower Flow Rate
135 GPM
Maximum Water Make-Up
2.7 GPM
at designed capacity
Maximum Evaporation
2.55 GPM
at designed capacity
Nominal Tower Flow Rate
255 GPM
Maximum Water Make-Up
5.1 GPM
at designed capacity
Maximum Evaporation
3.15 GPM
at designed capacity
Nominal Tower Flow Rate
255 GPM
Maximum Water Make-Up
6.3 GPM
at designed capacity
Maximum Evaporation
4.05 GPM
at designed capacity
Nominal Tower Flow Rate
405 GPM
Maximum Water Make-Up
8.1 GPM
at designed capacity
Maximum Evaporation
5.10 GPM
at designed capacity
Nominal Tower Flow Rate
510 GPM
Maximum Water Make-Up
10.2 GPM
at designed capacity
Maximum Evaporation
6.30 GPM
at designed capacity
Nominal Tower Flow Rate
630 GPM
Maximum Water Make-Up
12.6 GPM
at designed capacity
Maximum Evaporation
8.10 GPM
at designed capacity
Nominal Tower Flow Rate
810 GPM
Maximum Water Make-Up
16.2 GPM
at designed capacity
Maximum Evaporation
12.15 GPM
at designed capacity
Nominal Tower Flow Rate
1,215 GPM
Maximum Water Make-Up
24.5 GPM
at designed capacity
Maximum Evaporation
16.20 GPM
at designed capacity
Nominal Tower Flow Rate
1,620 GPM
Maximum Water Make-Up
32.4 GPM
at designed capacity
For more information about water make-up requirements and cooling tower systems call the Advantage Sales Department at 317-887-0729.
