The 99 LD-2000 is the most requested mechanical line leak detector built today. New engineering and the Vml 2-year warranty (after installation) make the 99 LD-2000 more attractive to station operators today than ever before. Not only is the 99 LD-2000 less expensive to own, it is faster and less subject to field and line variables than ever before! Integrated In-Line Check Valve / Pressure Relief A leaking check valve in the turbine, defective submersible pump pressure relief, or a defective bypass valve will allow the line system to depressurize, resetting the leak detector.