1. What is Cooling Tower Approach?

Definition: The cooling tower approach is the difference between the temperature of the cooled water leaving the tower and the ambient wet-bulb temperature.

Purpose: It's a key performance indicator for cooling tower efficiency - smaller approach values indicate better performance.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( A \) — Approach temperature (°F)
• \( T_{out} \) — Outlet water temperature (°F)
• \( T_{wb} \) — Ambient wet-bulb temperature (°F)

Explanation: The approach represents how closely the cooling tower can bring the water temperature to the wet-bulb temperature.

3. Importance of Approach Temperature

Details: Monitoring approach helps in:

• Evaluating cooling tower performance
• Identifying maintenance needs
• Optimizing energy efficiency
• Comparing tower performance under different conditions

4. Using the Calculator

Tips:

• Measure outlet water temperature at the tower basin
• Use accurate wet-bulb temperature for your location
• Typical approach values range from 5-15°F for well-designed towers

5. Frequently Asked Questions (FAQ)

Q1: What's a good approach value?
A: Generally, 5-10°F indicates good performance, but this depends on design conditions.

Q2: Why does approach increase over time?
A: Due to fouling, scale buildup, poor water distribution, or airflow problems.

Q3: Can approach be negative?
A: No, water cannot be cooled below the wet-bulb temperature.

Q4: How does approach relate to range?
A: Range is inlet-outlet temp difference, while approach is outlet-wetbulb difference.

Q5: When should I be concerned about approach?
A: When it increases by 3-5°F above design value, indicating performance degradation.