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A novel LHP, in which the wick is separated from the heating surface, has been proposed. And then, a steam chamber is formed, which can effectively use the pressure head of evaporation. This work is to optimize the key parameters in order to further improve the performance of such a novel LHP. A mathematical model, based on the node analysis method, had been established, which was validated against the experimental data. The height of steam chamber, the type of working fluids, and the material of wick were identified as key parameters to be optimized. The heating surface temperature, which was the highest temperature, and the start-up time were selected as the key performance indicators. Results showed there existed an optimal height of steam chamber (3mm) and charging ratio (55%) to achieve the lowest heating surface temperature and the shortest start-up time. For different working fluids, ammonia showed the best performance, followed by acetone, ethanol, and water. And the ceramic wick, with low thermal conductivity, demonstrated a better performance than the steel-nickel wick and copper wick with high thermal conductivity.