This experimental study aimed to validate the integration of a gravitational loop heat pipe (GLHP) with respect to a gas fireplace insert. The GLHP was utilized to enhance the efficiency of the fireplace by preheating the combustion air with waste heat from flue gases. The experiment involved monitoring key parameters such as vapor and condensate temperatures and absolute pressure within the LHP. The results demonstrated that a filling volume of 0.1 L of water in the LHP allowed for successful operation, while exceeding 0.2 L resulted in flooding and decreased system efficiency. Challenges related to vapor production and condensate return were identified, suggesting the need for further research and design improvements. The experimental verification confirmed the feasibility of implementing the gravitational LHP in a gas fireplace insert and emphasized the importance of optimizing vapor production and condensate return mechanisms. This study contributes to the advancement of thermal management strategies and provides valuable insights for enhancing the design and performance of such systems.
