Cooling Tower Sizing Calculator
The Cooling Tower Sizing Calculator finds the tower range, approach, and effectiveness for a heat-rejection duty at a design wet-bulb. Example: for a 500 kW heat-rejection duty at a 28 °C design wet-bulb, Heat rejection = 142.17 TR, Range = 5.5 °C, Approach = 1.5 °C, Effectiveness = 0.79 (per CTI STD-201 | ASHRAE 2021 Ch.39 | ASHRAE 90.1 | ASME PTC 23).
How it works
Computed from your inputs per CTI STD-201 | ASHRAE 2021 Ch.39 | ASHRAE 90.1 | ASME PTC 23.
Worked example (HVAC & Cooling)
Inputs: a 500 kW heat-rejection duty at a 28 °C design wet-bulb.
| Result | Value |
|---|---|
| Heat rejection | 142.17 TR |
| Range | 5.5 °C |
| Approach | 1.5 °C |
| Effectiveness | 0.79 |
Computed live by WorkHive's calculation engine; standard: CTI STD-201 | ASHRAE 2021 Ch.39 | ASHRAE 90.1 | ASME PTC 23.
How to use this calculator
- Enter the figures for the duty you are sizing: the worked example below uses a 500 kW heat-rejection duty at a 28 °C design wet-bulb.
- The calculator returns Heat rejection, Range, Approach, Effectiveness, computed per CTI STD-201 | ASHRAE 2021 Fundamentals.
- Check the worked example to confirm the method matches how you would do it by hand, then run your own numbers in the interactive tool.
FAQ
What is a cooling tower sizing calculator range approach?
The Cooling Tower Sizing Calculator is a free online tool that computes finds the tower range, approach, and effectiveness for a heat-rejection duty at a design wet-bulb. It shows the formula and a fully worked example so you can check the method, not just the number.
How is it calculated?
The result is computed from your inputs following CTI STD-201 | ASHRAE 2021 Fundamentals. The worked example on this page shows a real computation with real numbers.
Is the calculator free?
Yes. WorkHive's engineering calculators are free to use, no sign-up needed for the tools. WorkHive is a free, offline-first maintenance platform built for Philippine industrial plants.
Run it on your own numbers
Open the interactive Cooling Tower Sizing Calculator in WorkHive: free, no sign-up needed for the calculators.