The present paper focuses on Loop Heat Pipes (LHPs), which are passive two-phase cooling systems well suited for electronics cooling. Based on a validated and physics-based one-dimensional (1D) numerical model the steady-state performance of Loop Heat Pipes is assessed. By varying the ambient temperature, charging mass of coolant, and condenser cooling conditions, the performance of the LHP system under various operating conditions has been determined and its operational limits are assessed. The viscous limit, capillary limit, entrainment limit, and heat leakage limits are all identified. These limits are studied for different geometrical parameters and coolant properties. It is shown how geometrical parameters and cooling conditions of the condenser play a key role to achieve a wide feasible operating region for the LHP under investigation.