A transient model of a sorption refrigerator using activated carbon/methanol pair is presented. It is a non-uniform pressure model conformed by the mass, energy and momentum balance equations in cylindrical coordinates, for the activated coal bed contained in the adsorber. The results obtained from the simulation were suitably validated by the experimental information obtained from field test data and from data reported in the literature, presenting errors below 1.6% for each cycle step. The model allows to get data of temperature, pressure. density and gas velocity profiles in radial direction, as well as the solid temperature and the quantity of adsorbed methanol in the activated carbon bed in adsorption/evaporation and desorption/condensation steps. (C) 2009 Elsevier Ltd. All rights reserved.