FAQ

Are results certified?No — they're engineering estimates from catalog data and published correlations. Catalog entries marked "EN 12900" use manufacturer-published data, unverified by the manufacturer unless claimed.
Units?SI throughout: °C, kPa, kW, m³/s, kg/s, l/h.
Languages?English, Deutsch, Français, Español, Italiano, Polski, Nederlands, Svenska, Norsk, Suomi, 中文, 日本語 — picker in the top bar.
Billing?Prices in USD (see pricing); checkout can present your local currency. Cancel anytime; your saved systems are kept on downgrade.
Refrigerants?All CoolProp fluids including zeotropic blends (R448A-class); validated curve-fit fallback for R410A.
HVAC Builder · engineering results are estimates from catalog data and published correlations: ASHRAE, IAPWS-IF97, AHRI 540, EnergyPlus, CoolProp · weather data: PVGIS © European Union, JRC · contact: leads@hvacbuilder.app · bugs: bugs@hvacbuilder.app · Systems · Components · Suppliers · Privacy