Steam Systems Calculator | Plant Utilities

Steam Trap Loss Calculator

Estimate how much live steam your failed traps are losing, what it costs in boiler fuel each year, and the CO₂ that goes with it. Based on Napier's equation for steam flow through an orifice.

Inputs

Use the counts from your last trap survey. For how the formula works and how to find failed traps, see the steam trap failure cost guide.

Traps and steam

Cost of steam

Steam Loss per Blow-Through Trap
43.4 lb/h
24.24 × 114.7 psia × orifice². About $3,479 a year per trap.
Total Steam Lost
2,172,131 lb/yr
271.5 lb/h across all failed and leaking traps.
Annual Cost of Lost Steam
$21,743
At $10.01 per 1,000 lb of steam.
Wasted Fuel and CO₂
2,718 MMBtu
About 159 short tons of CO₂ a year if the boiler burns natural gas.

Formula Notes

Steam flow (lb/h) = 24.24 × P (psia) × D² (in). This is Napier's equation for steam escaping through a sharp-edged orifice to atmosphere. It is the maximum a fully open trap can pass. Traps that discharge into a pressurized condensate return lose less.

Steam cost ($/1,000 lb) = fuel price × (hsteam − hfeedwater) ÷ 1,000 ÷ efficiency. At 100 psig, 220°F feedwater, 80% efficiency and $8/MMBtu gas, steam costs about $10.01 per 1,000 lb.

Saturated steam enthalpy at your pressure: 1,189 Btu/lb. Net heat the boiler adds per lb: 1,001 Btu.

Use This Output in Context

This is a screening estimate for prioritizing repairs. It does not count lost condensate, makeup water and chemical treatment, or the process problems caused by traps that fail closed and back up condensate.

To see what the whole boiler costs to run, use the industrial boiler fuel cost calculator, and the boiler maintenance guide for the rest of the steam system checklist.