Top 10 Best Ac Load Calculation Software of 2026

Right-Suite Universal by Wrightsoft is a comprehensive HVAC design software suite renowned for its precise ACCA Manual J residential and light commercial load calculations, essential for accurate AC system sizing and energy efficiency. It integrates advanced tools for duct design (Manual D), equipment selection (Manual S), and 3D building modeling, streamlining the entire HVAC design process. Professionals use it to generate code-compliant reports, visualize heat gains, and optimize system performance from a single platform.

Carrier's Hourly Analysis Program (HAP) is a comprehensive HVAC software tool designed for detailed hourly load calculations, energy analysis, and system sizing in commercial and institutional buildings. It leverages ASHRAE-approved methods, extensive weather data, and customizable building parameters to simulate cooling, heating, and ventilation loads on an hour-by-hour basis throughout the year. HAP also integrates equipment selection from Carrier's catalog, enabling optimized system design and economic evaluations.

RHVAC from Elite Software is a specialized desktop application for performing accurate residential HVAC load calculations compliant with ACCA Manual J (8th Edition, Abridged). It enables detailed modeling of building envelopes, zones, infiltration, internal gains, and duct systems to determine precise heating and cooling loads. The software generates professional reports suitable for HVAC design, permitting, and energy code compliance, supporting both block and room-by-room methods.

CoolCalc is a cloud-based software solution designed for performing accurate ACCA Manual J-compliant cooling and heating load calculations for residential and light commercial buildings. It enables detailed room-by-room modeling, factoring in building orientation, construction materials, infiltration, and internal gains to determine precise equipment sizing needs. The tool generates professional PDF reports and integrates with popular HVAC design and quoting platforms for streamlined workflows.

Loadsoft from Carmel Software (carmelsoft.com) is a Windows-based desktop application designed for accurate HVAC load calculations compliant with ACCA Manual J 8th Edition (Abridged). It enables professionals to perform detailed room-by-room heat gain/loss analysis for residential and light commercial buildings, factoring in insulation, windows, infiltration, and local climate data. The software outputs professional reports for permitting, equipment sizing, and client documentation, with support for both sensible and latent loads.

LoadCalc.net is a cloud-based HVAC load calculation software that performs precise residential and light commercial AC load calculations using ACCA Manual J 8th Edition methods. Users input building geometry, insulation, occupancy, and climate data to generate accurate heating and cooling loads, equipment sizing recommendations via Manual S, and duct design via Manual D. It produces professional PDF reports compliant with building codes and is accessible via web browser without installation.

TRACE 3D Plus, developed by Trane Technologies, is a comprehensive building energy modeling software that excels in HVAC load calculations, whole-building energy simulations, and system optimization for commercial applications. It enables users to build detailed 3D models of structures, perform hour-by-hour load analyses using ASHRAE-compliant methods, and integrate with Trane's extensive equipment library for accurate sizing. Beyond basic AC loads, it supports advanced features like LEED compliance, life-cycle cost analysis, and renewable energy integration.

EnergyPlus is a state-of-the-art, open-source whole-building energy simulation program developed by the U.S. Department of Energy, capable of performing detailed AC load calculations as part of comprehensive building performance modeling. It simulates zone heating and cooling loads using advanced heat balance methods, accounting for transient effects, complex geometries, and integrated HVAC systems. While powerful for research and detailed analysis, it is not a streamlined tool for quick, standalone load calculations typically used in early design stages.

eQUEST, available at energy-design-tools.com, is a free whole-building energy simulation software based on DOE-2 that performs detailed hourly analyses of heating, cooling, lighting, and other loads. For AC load calculations, it models peak cooling loads through comprehensive simulations incorporating weather data, building geometry, internal gains, and HVAC systems. While not a standalone load calc tool like Manual J-compliant software, it excels in integrating load estimates with full annual energy performance predictions.

OpenStudio is an open-source software platform developed by NREL for whole-building energy modeling and simulation using the EnergyPlus engine. It enables users to create detailed 3D models, simulate energy performance, and perform HVAC load calculations as part of comprehensive building analysis. While capable of AC load calculations through its simulation capabilities, it is not a dedicated load calc tool and requires building a full energy model.