Hot in, cold out, and entering wet bulb → range, approach, and effectiveness %.
Last Updated: 06 May 2026
Range = hot water to tower − cold water leaving tower. Approach = cold water temperature − entering air wet bulb. Effectiveness = range ÷ (hot in − wet bulb). Use one consistent scale (°F or °C).
Range: 10 · Approach: 13 (°F)
Thermal effectiveness: 43.48% (0.4348 dimensionless)
Cooling Tower Efficiency Calculator helps you hot in, cold out, and entering wet bulb → range, approach, and effectiveness %. It is commonly used by engineers, lab users, field operators for cooling tower efficiency, cooling tower approach, cooling tower range.
Thermal model
For a counterflow-style mental model:
- **Range** = hot water temperature to the tower minus cold water leaving the tower.
- **Approach** = cold water temperature minus **entering air wet-bulb** temperature.
- **Effectiveness** (dimensionless, shown as %) = range ÷ (hot water in − wet bulb).
All three temperatures must use the same unit (°F or °C). This is a planning and training shortcut, not a vendor performance guarantee.