A mathematical model is developed for a novel arrangement proposed in order to cope with the drawbacks originating from the inefficient heat and mass transfer in adsorption heat pumps. The zeolite, used as the adsorbent, is envisioned to be synthesized on the surfaces of heat exchanger tubes as continuous coatings, which was also achieved experimentally. Simplifications regarding the boundary conditions are made by using the scaling method and a finite difference scheme is employed for the solution of the resulting differential equations to determine the variation of the temperature of the adsorbent as well as the concentration of the adsorbate within the adsorber. The typical restrictions of adsorption heat pumps are observed to be removed to a great extent and the duration of a single cycle is shortened significantly. (C) 1999 Elsevier Science B.V. All rights reserved.