A fluid leak detector for detecting leakage in a pressurized fluid system having a closed fluid conduit, the fluid leak detector comprising: a first resistance temperature detector RTD disposed within said conduit and capable of sensing the ambient temperature of the fluid within said conduit; a second RTD disposed within said conduit downstream of said first RTD and responsive to a drive signal to elevate the temperature of said second RTD; a means for generating said drive signal in communication with said second RTD to drive said second RTD to a temperature above said ambient temperature; and a controller for detecting the flow of fluid through said conduit characterized in that said means for generating a drive signal for said second RTD further comprises an adjustable wheatstone bridge circuit wherein said second RTD represents an element in the bridge circuit responsive to said flow of fluid through said conduit and said flow of fluid is used to determine the existence of leakage in the pressurized fluid system, said fluid leak detector further comprising: an analog to digital converter in communication with said first RTD, said second RTD and said controller for detecting the flow of fluid through said conduit, said analog to digital converter configured to sense said elevated temperature and generate a corresponding digital signal to said controller, said digital signal used to determine the existence of leakage in the pressurized fluid system. a first resistance temperature detector RTD disposed within said conduit and capable of sensing the ambient temperature of the fluid within said conduit; a second RTD disposed within said conduit downstream of said first RTD and responsive to a drive signal to elevate the temperature of said second RTD; a means for generating said drive signal in communication with said second RTD to drive said second RTD to a temperature above said ambient temperature; and a controller for detecting the flow of fluid through said conduit characterized in that said means for generating a drive signal for said second RTD further comprises an adjustable wheatstone bridge circuit wherein said second RTD represents an element in the bridge circuit responsive to said flow of fluid through said conduit and said flow of fluid is used to determine the existence of leakage in the pressurized fluid system, said fluid leak detector further comprising: an analog to digital converter in communication with said first RTD, said second RTD and said controller for detecting the flow of fluid through said conduit, said analog to digital converter configured to sense said elevated temperature and generate a corresponding digital signal to said controller, said digital signal used to determine the existence of leakage in the pressurized fluid system. an analog to digital converter in communication with said first RTD, said second RTD and said controller for detecting the flow of fluid through said conduit, said analog to digital converter configured to sense said elevated temperature and generate a corresponding digital signal to said controller, said digital signal used to determine the existence of leakage in the pressurized fluid system.