Cooling Tower Concentration Ratios Calculator

How the cooling tower concentration ratios calculator works

Conductivity cycles = circulating conductivity ÷ makeup conductivity. The separate water ratio is makeup volume ÷ (blowdown + other counted non-evaporative liquid loss). Their signed difference is shown; a zero denominator makes the relevant ratio unavailable.

Conductivities must use compatible units and compensation. The water ratio assumes counted liquid losses leave at circulating concentration, evaporation carries no dissolved constituent and there are no other sources/sinks. It is not automatically equivalent to the measured conductivity ratio. No chemical dose, concentration setpoint, corrosion limit or microbial-safety decision is made.

Quantities use the stated units and finite bounded inputs. Whole purchases round up under the documented model; cost components round half-up to cents before totals are summed. Undefined ratios stay unavailable. π and logarithms use normal numeric precision. Display rounding does not alter the entered assumptions.

Worked example

Conductivities of 1,200 and 300 give a ratio of 4. A 100 m³ makeup volume over 20 m³ blowdown plus 5 m³ other liquid loss also gives 4. Increasing circulating conductivity to 1,500 makes its ratio 5 while the volume ratio stays 4.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

• EPA Water Efficiency Management Guide Mechanical Systems