Complex machinery like spacecraft, aircraft, or chemical plants are equipped with fault detection and diagnosis systems. Due to their safety-critical nature, such diagnosis systems have to undergo rigorous Verification and Validation (V&V). In this paper, we present a tool to support V&V of system health models that have been developed using TEAMS. Our tool has been developed around the paradigms of cross validation, where diagnosis results of the TEAMS model are compared with results of other, more advanced reasoners, automatic fault scenario generation to support extensive testing and coverage analysis, and parametric model analysis to enrich test sets and for robustness and sensitivity analysis. We present this tool architecture on a case study using the NASA cryogenic fuel loading facility.