An experimental investigation was performed on a solar air heater with different configurations. The configurations included testing the single- and double-pass solar collectors with normal and perforated covers and with wire mesh layers instead of an absorber plate. Design and analysis of experiment was used to develop a model for the tested solar air heater and IBM's Statistical Package for the Social Sciences software was used to analyze the model. Strong agreement was found between the results obtained from the theoretical and experimental investigations. Both methods suggested the same configuration for attaining the highest thermal efficiency from the system, i.e., a double-pass solar collector with a quarter-perforated cover with 3-cm hole-to-hole spacing and a mass flow rate of 0.032 kg/s. (C) 2015 Elsevier Ltd. All rights reserved.