Cooling Tower Tons A cooling tower ton is defined as: 1 cooling tower ton = 1 TONS evap = 1 TONS cond x 1.25 = 15000 Btu/h = 3782 k Calories/h = 15826 kJ/h = 4.396 kW The equivalent ton on the cooling tower side actually rejects about 15000 Btu/h due to the heat-equivalent of the energy needed to drive the chiller's compressor.