Development of An Integrated Heating, Ventilation, Cooling and Dehumidification, System for Residences.

72200-Inadequate fresh air ventilation and poor indoor humidity control are two of the biggest problems in residential buildings. Both leaky older homes and more energy efficient newer homes often have problems maintaining adequate indoor comfort and air quality. Conventional air conditioning systems are not capable of providing the proper balance of cooling and dehumidification under varying outdoor conditions, and stand-alone dehumidifiers reduce overall system efficiency. This project will develop a cost-effective package of refrigeration components and controls that will provide the capability to meet changing latent and sensible loads, and provide fresh air ventilation, while using less energy than air conditioners with stand-alone dehumidifiers. The package will operate with conventional high efficiency furnaces, will be familiar to building trades, and will be easy to install. Phase I selected and designed key components (evaporator and subcooling coils), assembled and laboratory tested a prototype system to verify capabilities, and developed a system control strategy. Results indicate that moisture removal rates of about 51 to 55 liters per day during humid weather spells could be achieved, approximately two to four times more than a conventional single-speed central air conditioner. Phase II will further optimize the system for both cost and performance, package the components for ease of installation, develop integrated system controls, field test the system, and initiate technology transfer activities. Commercial Applications and Other Benefits as described by awardee: The integrated system should be well suited for controlling indoor temperature and relative humidity, along with providing fresh air ventilation, in single-family and small commercial applications located in humid regions. Since over three-quarters of the U.S. population is located in climates with high humidity, the market is substantial. Preliminary energy savings estimates suggest that the proposed system can provide improved comfort while saving 20% (650 kWh/year) of typical cooling and dehumidification energy usage, resulting in potential cumulative national energy savings of 162.5 GWH per year. In addition, the system should reduce the potential for mold growth, thereby reducing insurance claims.