Film-forming amines, and, more specifically, Z-N-9-octadecenylpropane-1,3-diamine (OLDA), are efficient corrosion inhibitors that are widely used in industrial closed-loop water systems. The active compound adsorbs on the metal surface and protects the substrate from corrosion. While the inhibitor steadily gains popularity in the industry, its bonding mechanism with metallic surfaces is not yet completely understood, limiting its applicability. Herein, we link the adsorption behavior of OLDA to the thermal gradient on the substrate and propose the thermoelectric surface charge created by the gradient as a determining factor for the adsorption, and, thus, efficiency of OLDA as a corrosion inhibitor.