Cooling Tower Range & Approach Calculator
Range, approach and effectiveness of a cooling tower from its three temperatures.
Approach is the tower's quality metric — chasing the last 1 °C of approach roughly doubles tower size. Every 1 °C colder condenser water ≈ 2–3% chiller energy saved.
Formula
Cooling Tower Range & Approach Calculator is a free cooling tower approach for HVAC designers, technicians and energy auditors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Cooling Tower Range & Approach Calculator
Range, approach and effectiveness of a cooling tower from its three temperatures. The calculation implements Range = T_in−T_out; Approach = T_out−T_wb; ε = R/(R+A) (CTI ATC-105; Cooling Technology Institute). Approach is the tower's quality metric — chasing the last 1 °C of approach roughly doubles tower size. Every 1 °C colder condenser water ≈ 2–3% chiller energy saved.
How to use Cooling Tower Range & Approach Calculator
- 1Enter Hot water in in °C.
- 2Enter Cold water out in °C.
- 3Enter Ambient wet-bulb in °C.
- 4Read Range, Approach, Effectiveness instantly — no submit button needed.
Why use Cooling Tower Range & Approach Calculator?
- ✓Implements the standard formula — Range = T_in−T_out; Approach = T_out−T_wb; ε = R/(R+A)
- ✓Reference cited on-page: CTI ATC-105; Cooling Technology Institute
- ✓Built-in engineering verdict flags out-of-range results instantly
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Cooling Tower Range & Approach Calculator use?+
It computes Range = T_in−T_out; Approach = T_out−T_wb; ε = R/(R+A), per CTI ATC-105; Cooling Technology Institute. The formula is displayed under the result.
What should I keep in mind when using this calculator?+
Approach is the tower's quality metric — chasing the last 1 °C of approach roughly doubles tower size. Every 1 °C colder condenser water ≈ 2–3% chiller energy saved.
Is this based on ASHRAE methods?+
The calculations follow the standard ASHRAE/ISHRAE formulations cited under the result, simplified where industry practice does the same. For permit-grade design, confirm with the full code procedure.
Is the Cooling Tower Range & Approach Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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