Center for the Built Environment

Using fans alone or in coordination with HVAC systems to cool people offers several significant enhancements compared to conventional HVAC systems, including improved thermal comfort, indoor air quality, air distribution, energy savings, and initial cost savings. Despite the numerous benefits of fans and fan-integrated systems, comprehensive resources are unavailable to guide engineers and architects in designing and implementing such systems. The purpose of this guideline is to address this gap and provide practitioners with valuable materials and answers to common questions. What are the available fan options? Various fan types are available in the market, such as ceiling fans, desk fans, and pedestal fans. This guideline provides a comprehensive overview of the criteria for fan type selection. These criteria cover blade characteristics, fan size, airflow patterns, fan performance metrics, motors and drives, power and efficiency, and control strategies. Ceiling fans are generally preferred for their higher efficiency, control and effectiveness, but cost, flickering and fixed location are limitations. This guideline can assist users in selecting suitable fan types based on individual building characteristics and specific application needs. How to integrate fans with my existing AC system? Adequate fan choice mainly depends on design intents, space characteristics, and HVAC operation strategies. This guidebook discusses which HVAC systems can be integrated with fans. With well-defined design intent, the guidebook provides a step-by-step process for determining the number and size of fans and their layout, ensuring proper fan installation, and integrating the fans with the control of the HVAC system. How do we implement and operate fans-integrated systems? Designing a successful fans-integrated system involves more than adding fans to a building. This guidebook assists building designers and operators by helping them adjust appropriate settings in chillers, air handling units, environmental conditions, and operation strategies. This optimization maximizes energy savings while ensuring occupants' comfort within the building. Additionally, the guidelines explore HVAC systems design that can enhance air distribution effectiveness and minimize construction costs. Most importantly, the guidelines outline a transformation strategy for transitioning from conventional air conditioning to a fan-integrated system with minimal disruption to occupants. This comprehensive approach ensures a smooth and efficient integration of fans into the existing air-conditioning infrastructure. Which design tools and case studies are available? This guidebook recommends using the and the CBE Thermal Comfort Tool CBE Ceiling Fan Design Tool. These tools enable users to define the comfort zone with elevated air speed and determine the optimal arrangement of ceiling fans based on room conditions specified by the users. In addition, the guidebook highlights relevant codes and standards related to environmental conditions, fan testing procedures, fire safety, and seismic requirements (subject to variations in different countries' regulations). Furthermore, we presented several case studies of buildings successfully implementing the fan-integrated HVAC system. We released two versions of our guidebook online: the Practitioner Summary and the Full Guide. These resources support selecting, designing, constructing, operating, and implementing fans and fans integrated HVAC systems. The Practitioner Summary offers a concise overview (~15 pages) of key considerations for building practitioners, providing brief descriptions of the fan-integrated system. In contrast, the Full Guidebook provides a more comprehensive exploration (~70 pages) of the fan and fan integrated system, including real building references, catering to users from diverse backgrounds. So we expect that many readers, after studying the Practitioner Summary, will move to sections of the Full Guidebook that are relevant to their work. Fans and fans-integrated HVAC systems will result in more sustainable and healthy buildings.