Cooling Tower Water Planning
A cooling tower removes heat by moving air across warm circulating water. Part of that water evaporates. A smaller part may leave as drift. Another part must be discharged as blowdown, so mineral concentration stays controlled. This calculator turns tower tons into practical water demand. It helps engineers, facility managers, and students estimate makeup water before a system is operated.
Why Tons Matter
One cooling ton represents heat removal capacity. Towers reject the equipment heat plus added compressor heat. That is why the heat rejection factor matters. A higher factor raises the effective heat load and increases evaporation. The circulation rate also matters because it sets tower range. When a measured range is available, the tool can use it directly.
Main Loss Types
Evaporation is usually the largest loss. It depends on circulation flow and temperature range. Drift is water carried out with the leaving air. Modern eliminators keep drift low, but it should not be ignored. Blowdown is controlled discharge. It prevents scale, corrosion, and fouling caused by dissolved solids.
Cycles and Makeup
Cycles of concentration compare minerals in circulating water with minerals in makeup water. Higher cycles reduce blowdown. Very high cycles may require better treatment, monitoring, and chemical control. Lower cycles increase water use and sewer cost. Makeup water equals evaporation, drift, and blowdown. A safety allowance can be added for real site variation.
Good Use Cases
Use this page during early design, retrofit studies, and operating reviews. It can compare different cycles, drift rates, and schedules. It also supports cost checks when water and sewer prices are known. For best results, use measured flow and range from field data. For planning, typical assumptions are acceptable. Always verify final values with local codes, treatment limits, and equipment data.
Reading the Result
The result shows hourly rates, period gallons, discharge, and estimated cost. It also shows computed range when no measured range is entered. A high blowdown value may suggest low cycles. A high evaporation value may suggest heavy heat load or long operating time. Use exports to save cases and compare operating choices. Repeat the calculation after water treatment changes, seasonal shifts, or load changes to keep budgets and maintenance plans aligned well.