A method of determining the status of a fluid cooled microwave ablation system is provided including providing an electrical current to a pump to pump fluid through an ablation system along a fluid path to cool the ablation system, measuring an electrical current drawn by the pump, and determining a status of the ablation system based on the measured electrical current. In another aspect of the disclosure, an ablation system is provided including an ablation probe defining a fluid path for circulation of fluid therethrough, a generator configured to supply energy to the ablation probe for treating tissue, a pump configured to pump fluid through the fluid path of the ablation probe to cool the ablation probe, a sensor configured to measure an electrical current drawn by the pump, and a computing device configured to determine a status of the ablation system based on the measured electrical current.