Total Heat Airflow Calculator (Enthalpy)
Total (sensible + latent) duty from airflow and enthalpy difference — coil selection math.
Enthalpy method captures both sensible and latent in one stroke — this is exactly how a coil schedule's 'total capacity' line is computed.
Formula
Total Heat Airflow Calculator (Enthalpy) is a free total heat formula for HVAC designers, technicians and energy auditors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Total Heat Airflow Calculator (Enthalpy)
Total (sensible + latent) duty from airflow and enthalpy difference — coil selection math. The calculation implements Q = ρ·V̇·Δh (US: BTU/h = 4.5 × CFM × Δh) (ASHRAE Fundamentals — psychrometric processes). Enthalpy method captures both sensible and latent in one stroke — this is exactly how a coil schedule's 'total capacity' line is computed.
How to use Total Heat Airflow Calculator (Enthalpy)
- 1Enter Airflow in L/s.
- 2Enter Entering air enthalpy in kJ/kg.
- 3Enter Leaving air enthalpy in kJ/kg.
- 4Read Total duty, Tonnage instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Total Heat Airflow Calculator (Enthalpy)?
- ✓Implements the standard formula — Q = ρ·V̇·Δh (US: BTU/h = 4.5 × CFM × Δh)
- ✓Reference cited on-page: ASHRAE Fundamentals — psychrometric processes
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Total Heat Airflow Calculator (Enthalpy) use?+
It computes Q = ρ·V̇·Δh (US: BTU/h = 4.5 × CFM × Δh), per ASHRAE Fundamentals — psychrometric processes. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Enthalpy method captures both sensible and latent in one stroke — this is exactly how a coil schedule's 'total capacity' line is computed.
Is this based on ASHRAE methods?+
The calculations follow the standard ASHRAE/ISHRAE formulations cited under the result, simplified where industry practice does the same. For permit-grade design, confirm with the full code procedure.
Is the Total Heat Airflow Calculator (Enthalpy) free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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