Calculation sequence
Step-by-step method
- Confirm the calculation boundary, units, and source of every input.
- Apply the displayed equation to the entered values.
- Review the result against governing criteria and documented uncertainty.
PlumbingIntermediateLiquid Fuels
Liquid-Propane Consumption-Rate Calculator
Calculate liquid-propane use from useful heat rate, conversion efficiency, and user-entered heating value.
Why it matters: A transparent formula keeps the user-entered hydraulic, gas, or storage basis available for technical review.
Calculated result
Engineering evaluation
Liquid-propane consumption rate (q_f)6.429 gal/h
- Required fuel input rate (H_in)
- 588,235.3 Btu/h
Engineering interpretation
The entered useful load, efficiency, and heating value require 6.428801 gal/h.
Important limitations
- Confirm higher/lower heating-value basis, density, temperature, burner efficiency definition, cycling, auxiliaries, altitude, storage, and exact supplier fuel properties.
Engineering knowledge center
Understand the calculation—not just the answer
Governing relationships
H_in=H_u/η
q_f=H_in/HV
Current substitution
q_f=500000/(0.85×91500)=6.428801.
Equation legend
Inputs and calculated quantities
- H_u
- Useful heat rate — Btu/h or kW
- η
- Conversion efficiency — 0–1
- HV
- Liquid-propane heating value — Btu/gal or kWh/L
- q_f
- Liquid-propane consumption rate — gal/h
- H_in
- Required fuel input rate — Btu/h
Applications
How this calculation is used
Building design
Screen a documented system relationship without embedding a protected design table.
Construction
Check submittal and field values using the same visible inputs.
Commissioning
Reconcile measured and scheduled conditions before professional disposition.
Quality controls
Assumptions and limitations
Assumptions
- Inputs describe one documented system boundary and compatible operating condition.
- All values use the displayed symbols and one consistent unit system.
Limitations
- This screen does not establish code compliance, final design, equipment selection, or acceptance.
- Adopted codes, local criteria, manufacturer data, uncertainty, and professional judgment remain controlling.
Field use
Verification procedure
- Identify the calculation boundary and source of each input.
- Record representative values with compatible pressure, temperature, flow, and time bases.
- Review the result against the adopted criteria, manufacturer data, and uncertainty.
Common engineering mistakes
- Mixing standard and actual gas volumes or gauge and absolute pressures.
- Treating an arithmetic screen as a code-sizing table or hidden acceptance criterion.
Technical basis
References and source standards
- International Plumbing CodeAdopted edition and local amendments govern; protected sizing tables are not reproduced.
- American Society of Plumbing EngineersPlumbing engineering-method context; verify licensed references and project criteria.
- NIST SI and Unit GuidanceUnit and dimensional-conversion basis.
Engineering calculation disclaimer
These engineering tools are provided for educational, preliminary evaluation, field verification, and commissioning support. Results depend on the accuracy of user-entered information and the assumptions stated for each calculation. Every colored status and comparison is a screening indicator only; project criteria, contract requirements, applicable codes, manufacturer instructions, measurement uncertainty, and authorized engineering judgment govern. The tools do not replace project-specific engineering analysis or the judgment of a licensed professional engineer.
Read the full use and limitation statement