A direct heat exchange system using zeolite 13X-water working pairs is expected as an effective process to generate steam more than 150 degrees C from water below 100 degrees C. As a basic study, steam at 100 degrees C from water at 80 degrees C was investigated. The effects of the direction of feeding water in the adsorption process were experimentally investigated. The experimental results for the feeding from the bottom show that mass of generated steam reached almost 90% of the theoretical value obtained by heat mass balances. However, the performance, that is, the mass ratio of generated steam to the inlet water was around 6.5% because an abundance of water should be introduced to get contact between zeolite particle and water. Feeding water from the top was, therefore, investigated to increase the performance of steam generation with various nozzle configurations. Although the mass of the product steam was less than that for feeding water from the bottom, the mass ratio was improved to 13% by using 14 nozzles. This is because the nozzle installation enlarged the contact area between water and zeolite with a small amount of water.