iOS · iPhone & iPad HVAC Calculator & Ductulator
A field toolkit for HVAC/R technicians. Duct sizing, superheat and subcooling, airflow checks, load estimates, and PDF job reports — fully offline, no account, no login.
Ductulator
CFM and friction rate in, round and rectangular duct sizes out — with velocity limits checked for supply, return, and branch runs. Sheet metal and flex.
Refrigerant charge
Superheat and subcooling against a target, for R-410A, R-32, R-454B, R-22, R-134a, and R-407C. PT data computed from NIST reference equations — enter any pressure.
Airflow
Temperature-rise CFM, the three fan laws, and the 350–450 CFM-per-ton check — confirm airflow before touching the charge.
Jobs & PDF reports
Save readings to a job and export a service report with your name and company on it, ready to hand over with the invoice.