Start with your task
Check heating and cooling
Check motor current
Follow the water circuit
Use refrigerant measurements
HVAC Calculators 26
Electrical Calculators 28
About These Calculators
All calculations follow published engineering standards: ASHRAE 90.1, 62.1, and Handbook of Fundamentals for HVAC; NEC 2023 (NFPA 70) for US electrical; IEC 60364 for international electrical. Results are for preliminary engineering use — verify with full Manual J, Manual D, or detailed load analysis before equipment selection. See our Methodology page for formula references.