Accurate heating and cooling load calculations are the foundation of HVAC equipment sizing. This resource center organizes HVACProSales technical guides by calculation method, building-load input, and supporting engineering topic.
Choose the Right Load-Calculation Path
- Manual J residential load calculations
- Manual N commercial load calculations
- ASHRAE cooling-load methods
Evaluate the Major Building Loads
- Window and solar heat-gain loads
- Infiltration and ventilation loads
- Building-envelope heat transfer
- Internal heat gains
Account for Sensible and Latent Conditions
Load calculations should address both temperature and moisture. Use the psychrometric resources below when reviewing indoor design conditions, ventilation, dehumidification, and coil performance.
Professional Sizing Workflow
- Confirm the applicable calculation standard and project scope.
- Document outdoor and indoor design conditions.
- Measure envelope, glazing, orientation, occupancy, ventilation, and internal-load inputs.
- Calculate room-by-room and whole-building sensible and latent loads.
- Select equipment using verified performance data at the actual design conditions.
- Review duct, airflow, controls, electrical, and commissioning requirements before installation.
Important: This hub is an educational navigation resource. Final equipment sizing should be completed or reviewed by a qualified HVAC professional using the applicable standards, local requirements, and current manufacturer performance data.