The water molecules adhere to the surface of the silica gel. The silica gel is a very porous component with a high number of voids that may contain water when needed. Silica gels of two types of PSD are frequently used for commercial purposes i. e. Type A and B which have different shapes of adsorption isotherms of water vapor.The most influential parameter is the operating temperatures, followed by water flow rates. Cycle time is less influential in quantitative terms but qualitatively is very important. Adsorber/desorber as a part of the two-bed single-stage adsorption heat pump is discussed.