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HVAC Tech

The HVAC technician's field calculator — fully offline.

Built for the field

Refrigerant and airflow math that works with no signal — on a rooftop, in a mechanical room, anywhere. No account, no cloud, no tracking.

  • Superheat (target & actual)
  • Subcooling (target & actual)
  • Refrigerant P/T Chart
  • Delta-T (temperature split)
  • Duct Sizing (CFM → size)
  • Airflow & Tonnage / Fan laws

R-410A · R-22 · R-32 · R-454B · R-134a · R-404A · R-407C

HVAC Tech Pro

All calculators are free. HVAC Tech Pro (one-time purchase, no subscription) unlocks unlimited saved jobs and PDF / share export.