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The trend to miniaturize electronic devices requires novel high performance cooling techniques. Heat pipes (HP), loop heat pipes (LHP) and capillary pumped loops (CPL) have proven their potential to remove high heat fluxes. Here, a novel two-loop system is presented, similar in design to CPLs but with a secondary buoyancy driven two-phase loop. Specific advantages compared to a standard CPL are: the working fluid can be filled in a non-degassed state due to the large system tolerance towards non-condensable gases; easy filling procedure; easy start-up; the amount of fluid in the system can be varied in a broad range without affecting the heat transfer performance. For the present study methanol was used as working fluid and three different inverted meniscus type evaporators have been employed. A maximum heat transfer rate of 35W/cm2 at the evaporator has been obtained. The maximum heat transfer coefficient was 16.5 W/(cm2 K) at a very small wall superheat of 0.45 °C. Oscillations of pressure, temperature and the liquid vapour interface occurred for all experimental conditions. These oscillations triggered a periodical wetting/dewetting process within the evaporator structure which obviously contributes to an enhancement of the evaporative heat transfer coefficient.