Cryogenic loop heat pipes (CLHPs) are effective and efficient cryogenic heat transport devices suitable for many space and terrestrial applications. Due to the complexity of its structure, the startup and operation of CLHPs might be influenced by the relative position of different components; however, little work has been done on this aspect. In this work, a miniature CLHP with nitrogen as the working fluid employing an auxiliary loop to assist the supercritical startup was developed. The effect of the layout of the secondary loop line and the gas reservoir on the startup and operation of the CLHP was experimentally investigated. The experimental results show that the relative position of these components can affect both the startup and steady-state operation of the CLHP. The heat transport capacity of the CLHP can be increased considerably when the secondary loop line is connected to the middle or top of the primary compensation chamber. (C) 2013 Elsevier Ltd. All rights reserved.