System Design Load
Cooling and heating loads at the touch of a button
How Does It Work?
System-based design tailors HVAC load and sizing calculations to the specific system type and controls being used. By accounting for how each system operates, System Design Load delivers more accurate room loads, airflow rates, and system component sizing than generic load calculations.
Pricing: $1,055 US / $1,355 CAN
Why Choose System Design Load?
Advanced Load Calculation Methods
System Design Load v6 applies ASHRAE® Heat Balance cooling load procedures, peak heating load methods, and clear sky solar algorithms. It calculates ventilation airflow per ASHRAE Standard 62.1 (2004–2019), performs full psychrometric analysis corrected for altitude, and determines zone and coil loads for 12 monthly design days across 24 hours, automatically identifying peak conditions and true zone relative humidity.
Comprehensive Building & Environmental Analysis
The program models complex building geometry and exposures, including sloped roofs, skylights, and 16 building orientations. It analyzes solar and transmission effects from external and interior shading, window framing, and building rotation, as well as morning pulldown, return plenums, duct leakage, thermostat throttling range, and local design weather for over 7,000 global locations.
System, Equipment & Controls Modeling
System-based loads are calculated for fans, coils, terminals, chillers, and heating equipment. The software models supply and return fan horsepower and heat gain, draw‑thru and blow‑thru configurations, part‑load fan performance, dehumidification controls, economizers, humidifiers, and heat recovery. It supports a broad range of HVAC system types including VAV, VRF, fan coils, heat pumps, chilled beams, PTACs, and more.
Scheduling, Editing & Output Capabilities
Hourly scheduling is available for equipment, fans, thermostats, lighting, occupancy, and internal gains, with seasonal scheduling options. Global editing tools, easy building rotation, presentation‑quality graphics, and exportable outputs support efficient documentation. System Design Load v6 includes the same 3D building modeling features as HAP v6.
Key Features
System‑Specific Load & Sizing Intelligence
Tailors load calculations and sizing procedures to specific HVAC system types and controls, ensuring accurate results for systems with unique components and operating characteristics.
Flexible Design Detail—from Concept to Final Sizing
Supports both general load calculations for early design and advanced system‑based design when system details are known, allowing users to apply as much or as little modeling detail as needed.
End‑to‑End Building & System Definition
Combines detailed building modeling, global design weather data, and customizable construction inputs with system and control selection to produce high‑quality room, system, and component sizing results.
Resources
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