Following paper presents a comparative study of the indirect evaporative exchangers operating as heat recovery units, arranged in the counter- and cross-flow configuration. Presented analyses are carried out with particular emphasis on the condensation process that occurs in the product air channels of the exchangers. Several aspects related to the water vapor condensation are address. Those aspects include the identification of factors that influence the condensation process and analyzing those factors impact on different IEC exchanger configuration. Another issue is a performance comparison of the counter- and cross-flow exchanger for various inlet parameters and operating conditions. Performed analyses are based on the numerical simulations conducted with mathematical epsilon-NTU model of the heat and mass transfer. Presented model is validated against experimental data and the measurements taken at the test station. Achieved results showed that the counter-flow configuration has higher sensible and latent cooling potential than the cross-flow unit. Nonetheless, due to the technical limitation of the counter-flow configuration, the cross-flow exchanger achieved higher Energy Efficiency Ratio and is characterized by lower investment cost. (C) 2018 Elsevier Ltd. All rights reserved.