What is disclosed is an apparatus for determining the cooling characteristics of a cooling device used for transferring heat from an electronic device. The apparatus comprising a cooling device thermally coupled to a heat pipe. The heat pipe having an exposed surface for the selective application of heat thereon. A localized heat source is selectively applied to at least one region of the exposed surface. The heat source preferably capable of being varied both positionally relative to the exposed surface and in heat intensity. A heat shield is preferably positioned around the exposed surface of the heat pipe to isolate the operational cooling device from the localized heat source. A temperature detector repeatedly measures a temperature distribution across the exposed surface while the cooling device is in a heat transfer mode. The temperature distribution is then used to thermally characterize the cooling device.