We carried out experiments of repeated frosting/defrosting cycles while varying the heat exchanger inclination angles (0 degrees, 15 degrees, 30 degrees, and 45 degrees) of a louvered fin heat exchanger and analyzed the variations in thermal performance, residual water, and defrosting efficiency according to the heat exchanger inclination angle. For larger inclination angles, the heat transfer rate and pressure drop varied less during repeated cycling. The use of high inclination angles improved the drainage performance of the louvered fin heat exchanger and reduced the mass of its residual water. The defrosting efficiency varied less during repeated cycling for high inclination angles than for low inclination angles. (C) 2017 Elsevier Ltd. All rights reserved.