Calculate condensate return, steam supplied, steam not returned, or makeup water from a simplified steam mass balance in kg, g, lb or tonnes.
Condensate Return Formula
The calculator uses a simplified steam system mass balance. It assumes that steam supplied is accounted for by condensate returned plus makeup water. At steady state, steam not returned equals makeup water within this model. Real boiler makeup can also replace blowdown and other losses.
- SS = steam supplied
- CR = condensate return
- MW = makeup water
- SNR = steam not returned, consumed, or lost
Select the quantity to solve for and enter its two required inputs. Choose total mass, flow per hour, or flow per day and use the same period for every input. Values are converted to kilograms before solving and then converted to your selected result unit. An optional measured balance check reports disagreement without changing the solution.
- Condensate Return: calculated as steam supplied minus makeup water.
- Steam Supplied: calculated as condensate return plus makeup water.
- Steam Not Returned: calculated as steam supplied minus condensate return.
- Makeup Water: calculated as steam supplied minus condensate return.
Condensate Return Reference Values
Condensate return is often reviewed as a percentage of steam supplied. Higher return usually means less makeup water, less water treatment demand, and less heat lost from the system. The following bands are illustrative descriptions, not universal performance targets; suitable return depends on the process and condensate quality.
| Condensate Return Rate | General Interpretation | Typical Meaning |
|---|---|---|
| Below 50% | Low return | Large steam use to process, drain losses, leaks, or poor recovery |
| 50% to 75% | Moderate return | Some condensate recovery, but losses may still be significant |
| 75% to 90% | High return | Most condensate is recovered and reused |
| Above 90% | Very high return | More than 90% of supplied steam is measured as returned condensate |
The calculator supports these mass units:
| Unit | Equivalent in kg |
|---|---|
| 1 g | 0.001 kg |
| 1 kg | 1 kg |
| 1 lb | 0.45359237 kg |
| 1 tonne | 1000 kg |
Example Calculations
Example 1: Calculate condensate return
You supply 10,000 kg of steam and add 2,000 kg of makeup water. The condensate return is:
The condensate return is 8,000 kg.
Example 2: Calculate makeup water
You supply 5,000 lb of steam and return 3,750 lb of condensate. The makeup water is:
The makeup water is 1,250 lb. In this simplified balance, steam not returned is also 1,250 lb.
FAQ
Is makeup water always equal to steam not returned?
Not always. In this simplified steady mass balance, makeup water equals steam not returned because steam or condensate that does not come back must be replaced. In a real boiler system, boiler blowdown, venting, leaks, sampling, and measurement error can make the two values different.
Can this calculator be used for flow rates instead of total mass?
Yes. Select Flow per hour or Flow per day, then use that time basis for every input. For example, kg/h, lb/h, or tonnes/day are supported by combining a mass unit with the selected time basis. The mass balance works the same way for consistent flow rates.
Why does the calculator reject a negative result?
A negative result means the inputs do not fit the simplified balance. For example, condensate return cannot be greater than steam supplied if makeup water is being calculated as steam supplied minus condensate return. Check the units and the entered values before recalculating.
