Under steady conditions, the rate at which the water leaves the make-up tank is equal to the rate of evaporation plus any small airborne droplets in the air discharge (i.e., drift)

Check the validity of this statement: 1% of circulating water evaporated for every 5 o C drop in water temperature

Hint: mass flow rate of air =0.0137*[x/(1+2)*specific volume]^0.5, unit of x is mmH2O