Depending on the heat flux increment in recent two decades, liquid cooling techniques in thermal management became one of the most preferred choices for electronics cooling technique, especially in military applications. As the complexity and numbers of cold plate increase, it necessitates examining the design of cold plate in details to prevent catastrophic failures both during operation and storage. In liquid cooling applications, there are many precautions taken to prevent mechanical failures caused by liquid thermal expansion. It is well known that liquids cannot be compressed or very small compression can take place due to their nature. In thermal expansion problems, there is an interaction between stagnant fluid and solid. They expand together because of increase in temperature. As a result, hydrostatic pressure increases due to thermal expansion of trapped liquid even at small temperature increment. Therefore, in liquid cooling applications, one of the easiest measures is the usage of relief valves to release excess pressure to protect the system or design from overpressure. In this study, one cold plate has been selected as a case study to investigate the behavior of cold plate in terms of hydrostatic pressure and stress variation depending on the alternating ambient temperature. In addition, before performing tests, FEM structural analysis has been carried out to design the experiment. Finally, hydrostatic pressure values exerted by trapped liquid have been measured at different locations depending on the temperature.