Architectural Designs

What are the steps in designing a HVAC system?

I know it depends on what the building is used for (Storage, School, etc.) but just in general what are the steps for a commercial building? I think you calc your max loads, divide into zones. Select your equipment & Install ductwork right?

Public Comments

1. Here are some of the steps your HVAC trade contractor should follow when designing the duct system: Calculate the building's heating loads and cooling loads. Select the proper size equipment for the for the building using a HVAC manual guide.This has to be done before duct sizes are calculated because the specific blower data will determine the duct sizing criteria. A scale drawing of the home's air distribution system is sketched to show equipment placement, register sizes and locations, air flows associated with each register, location and lengths of ducts. Determine the size of the ducts based on calculations and information about blower data, room size, and air flow following the procedures in the manual. It's important that the HVAC contractor properly sizes both the main trunk and branches of the duct systems. This will help make sure that each room will receive the appropriate amount of conditioned air. or you can try open this link for more technicalilty: http://www.facilitiesnet.com/bom/Mar04/Mar04HVAC.shtml
2. The following steps should be followed in the design and installation of the HVAC system : Determine room-by-room loads and air-flows using ACCA Manual J calculation procedures (or substantially equivalent). Layout duct system on floor plan, accounting for the direction of joists, roof hips, fire-walls, and other potential obstructions. Determine register locations and types, duct lengths, and connections required to produce layout given construction constraints. Size duct system according to ACCA Manual D calculation procedures (or substantially equivalent). Size HVAC equipment to sensible load using ACCA Manual S procedures (or substantially equivalent). Install equipment and ducts according to design specifications, using installation requirements and procedures from the Uniform Mechanical Code, the Air Diffusion Council, SMACNA, California Residential Energy Efficiency Standards, and manufacturers' specifications (Title 24); Using these procedures and those in Appendix A, the duct system should be substantially air tight. Charge the system appropriately, and verify charge with the evaporator superheat method or subcooling method (or substantially equivalent). Check for proper furnace burner operation and fire-box drafting. Test the system to ensure that it performs properly by determining (1) that the system is properly sized, (2) it does not leak substantially, and has either (3a) proper air handler fan flow, and proper plenum static pressures, or (3b) proper room and return air flows, and proper plenum static pressures.