An experimental technique, using liquid crystals and the transient method was developed to measure in-tube condensing local heat transfer coefficients. Measurements with R-12 inside a horizontal, smooth circular tube is presented. This article describes the experimental procedures lured to achieve a step change in the surface temperature with a special valve. The test section consists of a transparent glass tube observed from outside. The inside surface transient temperature response is measured by a thin layer of cholesteric liquid crystals. The color distribution of the liquid crystals is then translated through a digital color image processing unit into a surface temperature distribution. The local condensing heat transfer coefficients are obtained using a transient heat conduction analysis. Results for stratified flow regime are compared with results from the literature. This experimental technique provides a new tool for the measurement of the condensing local heat transfer. The technique is applicable to measurements of condensing local heat transfer coefficients inside noncircular passages with plain or enhanced surfaces, which are commonly employed in state-of-the-art and advanced phase-change heat exchangers.