Abstract: A cooling system for a heat source includes a heat source loop, a refrigerant loop, and a controller. The heat source loop provides a closed fluid path for a process fluid and fluidly connects a valve, a bypass leg and/or a heat exchange leg having a heat exchanger, and a pump. The process fluid is disposed within a portion of the loop and is subject to heat transfer from the heat source. The valve is disposed downstream of the heat source portion of the loop, wherein the valve is selectively operable to direct process fluid to the bypass leg and/or the heat exchanger leg. The refrigerant loop provides a closed fluid path for a fluid refrigerant and fluidly connects the heat exchanger, a refrigerant compressor, a refrigerant condenser, and a refrigerant regulator. The controller is in communication with the valve and is adapted to control the valve to regulate an amount of process fluid entering the bypass leg and the heat exchanger leg.