Residential air-conditioning equipment is typically optimized to provide sensible cooling. High-performance homes have lower sensible loads because of improved envelope performance, making the latent loads a larger portion of the required cooling. These high-performance homes (especially those in hot-humid climates) need an air-conditioning unit with a sensible heat ratio that simply is not available in current residential equipment. In the 2009 Residential Energy Consumption Survey, 8.4 million households (12%) in the Midwest and South responded that they use a dehumidifier. Of those, 3.6 million use their dehumidifier four to nine months a year, with another 1.6 million using their dehumidifier constantly year-round.

Through this research project, Steven Winter Associates seeks to research, develop, and evaluate an integrated heating, dehumidifying, and air-conditioning (HDAC) system to address the latent and sensible loads of high-performance homes with a single system. An alpha prototype with a sensible heat ratio variance greater than 20% will be developed and tested in a lab to optimize controls. Lessons learned will be used to refine the design of the system and two beta prototypes will be constructed. After lab testing is complete, installation, commissioning, and long-term testing of both beta prototypes will be conducted in occupied homes.