We presented ModulAr Semantic CAching fRAmework (MASCARA) that deployed Semantic Caching (SC) to perform a fast query processing based on Field Programmable Gate Arrays (FPGAs) accelerators. In addition of the accelerators, cache management plays an important role to address coalescing strategy and replacement policy so as to maximize the performance of FPGA caching. Therefore, in this paper, we present a coalescing heuristic with a new replacement function that leverages advantages of traditional strategies and overcomes their drawbacks. The proposed heuristic reduces response time, improves data availability, and saves cache space with respect to the semantic locality of query workload.