Enter the water flow rate and temperature difference into the calculator to determine the cooling tower capacity.

Cooling Tower Capacity Formula

The following formula is used to calculate a Cooling Tower Capacity.

CTC = 500 * Q * T / 12,000

  • Where CTC is the Cooling Tower Capacity (tons)
  • Q is the water flow rate (gallons/minute)
  • T is the temperature difference (F)

To calculate the cooling tower capacity in tons, multiply the water flow rate by the temperature differential, then divide by 12,000, then multiply by 500.

What is Cooling Tower Capacity?


A cooling tower capacity is a measure of the total tons cooling a cooling tower can perform. A 1-ton chiller is equal to 12,000 BTUs.

How to Calculate Cooling Tower Capacity?

Example Problem:

The following example outlines how to calculate Cooling Tower Capacity.

First, determine the water flow rate of the tower. For this example, the cooling tower has a water flow rate of 200 gallons per minute.

Next, determine the temperature differential of the cooling tower. For this cooling tower the difference is 50F.

Finally, calculate the Cooling Tower Capacity using the formula above:

CTC = 500 * Q * T / 12,000

CTC = 500 * 200 * 50 / 12,000

CTC = 416.66 tons /day