Best HAP Alternative for HVAC System Software
HAP vs Hysopt
Carrier’s Hourly Analysis Program (HAP) is well-known for calculating building heating and cooling loads and creating energy simulations. While it’s an industry staple for load estimation, it remains a static calculation tool — not a dynamic system simulator. Hysopt goes further, combining load calculation with full thermal, hydraulic, and control simulation to guarantee your HVAC system delivers the performance you expect.
What’s the Difference between HAP and Hysopt?
HAP is primarily designed for static load calculations and preliminary equipment sizing based on building demand. While it can give a first estimate of required capacities, it does not simulate real-world thermal and hydraulic behaviour, control strategies, or system balancing. This means designs based on HAP alone risk oversizing and reduced operational efficiency.
Hysopt takes you beyond demand estimation. By modelling the complete HVAC system, including hydraulics and controls, Hysopt ensures designs are right-sized, balanced, and optimised for both energy efficiency and comfort — all before installation.
- Integrated
- Core feature
- Yes
- Not included
- Built-in
- Not included
- Included
- Not available
- Automated
- Manual adjustments
- Proven outputs
- Limited scope
Why Engineers Choose Hysopt Over HAP
1. From Demand to Delivery
HAP gives you equipment sizing numbers. Hysopt ensures the entire system — pipes, pumps, valves, and controls — is configured to deliver those numbers in reality.
2. Detect Oversizing Early
Avoid costly oversizing caused by conservative load estimates. Hysopt dynamically tests and optimises your design before it reaches the site.
3. All-in-One Design & Simulation
No need to switch between load calculators and other tools — Hysopt integrates everything from demand estimation to control validation in a single platform.
Who Benefits from Switching to Hysopt
HVAC Design Engineers
Add hydraulic and control accuracy to your load calculations for systems that work first time.
Commissioning Managers
Reduce post-installation balancing and troubleshooting.
Energy & Sustainability Specialists
Prove system performance with transparent energy and CO₂ savings data.
How to Move from HAP to Hysopt
Making the switch is straightforward:
• Import relevant demand data from HAP into Hysopt
• Build a dynamic model with hydraulic and control layers
• Run simulations to test, optimise, and validate system behaviour
• Use Hysopt’s automated reporting to share results with stakeholders
- Integrated
- Not included
- Built-in
- Not included
- Included
- Not supported
- Modern, guided workflows
- More complex, static workflow
Frequently asked questions
Can Hysopt replace HAP?
Is Hysopt more accurate than HAP?
How does Hysopt improve on HAP’s results?
Is Hysopt easier to use than HAP?
Ready to see the Difference?
Make the switch from HAP to Hysopt today — and design HVAC systems that don’t just meet demand on paper, but deliver it in reality with maximum efficiency.
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