Boiler Makeup Water Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 26, 2026Boiler Makeup Water Calculator
Every kilogram of water that leaves a boiler system as blowdown, steam leaks, or unreturned condensate has to be replaced with freshly treated makeup water - and tracking that total highlights a real, ongoing cost most operators underestimate.
Formula: Makeup Water = Blowdown Rate + Other Losses
Example: 250 kg/hr of blowdown plus 100 kg/hr of other losses (leaks, venting, unreturned condensate) requires 350 kg/hr of makeup water.
How to Use This Calculator
- Enter the boiler's blowdown rate.
- Enter other water losses (leaks, vents, unreturned condensate).
Makeup water is not free water - it requires its own chemical treatment and has to be heated from scratch, which is exactly why reducing blowdown and improving condensate return both directly reduce this figure and the operating cost behind it.