Nothing in HVAC Builder is a proprietary correlation. Every relation the solver uses is published, and these are the publications — follow them if you want to check a number rather than take ours.
| ASHRAE Handbook — Fundamentals | moist-air psychrometrics and the air-side heat-transfer relations |
| IAPWS-IF97 | the water/steam saturation line and liquid-water properties |
| AHRI Standard 540 | the 10-coefficient compressor performance maps the catalog carries |
| EnergyPlus Engineering Reference | evaporative-media saturation effectiveness and the frost/defrost derating |
| CoolProp | refrigerant properties when the shared library is present |
| PVGIS (European Commission, JRC) | the measured typical meteorological years behind every weather-driven run |
Component data itself comes from the catalog: manufacturer-published figures where a supplier has listed them, generic or clearly-labelled synthetic entries otherwise. A listing's certification badge is the supplier's own claim unless it is marked verified.