Adequate ventilation of buildings with outside air is required for healthy indoor air quality; however, in a hot humid climate, the greatest load on air-conditioning is the latent heat (humidity) of the air that enters the building. Low cost, highly effective, energy recovery ventilators are needed, which condition incoming air by exchanging latent heat as well as sensible heat with the outgoing air. Elastomer bed heat exchangers have been shown to exhibit significantly greater heat transfer per unit of pressure drop over exchangers currently employed in energy recovery ventilators. Therefore, this project will develop an enthalpy coating for the elastomer bed heat exchanger, leading to heat exchanger operation with at least 65% latent effectiveness, at least 75% sensible effectiveness, and, at most, a pressure drop of 0.8 in. water, at a face velocity of 600 ft./min. In Phase I, desiccant coatings of elastomer sheets will be produced on a laboratory scale and tested for durability, residual tackiness, etc. The most suitable coatings will be made into laboratory scale enthalpy exchangers and tested in a laboratory ventilator for performance under hot humid conditions. Performance and cost calculations for both residential and commercial sized enthalpy exchangers will be conducted. Commercial Applications And Other Benefits as described by awardee: Higher performance, lower cost energy recovery ventilators using the elastomer bed energy exchangers should reduce energy consumption used in air-conditioning and improve indoor air quality in existing commercial and residential markets.