The　energy　consumption　of　data　centers　is　increasing　rapidly　with　the　development　of　technology.　In　order　to　reduce　the　energy　consumption,　free　cooling　technology　instead　of　the　conventional　refrigeration　system　is　feasible　in　the　cold　season.　In　the　present　work,　a　pump-driven　two　phase　cooling　system　which　is　an　excellent　free　cooling　technology　was　developed　and　the　prototype　was　investigated　experimentally.　The　experimental　results　show　that　the　efficiency　of　the　magnetic　pump　was　7.7%　at　the　motor　frequency　of　22　Hz,　the　cooling　capacity　of　the　system　was　able　to　reach　3.429　kW　and　9.241　kW　when　the　temperature　differences　between　indoor　and　outdoor　were　10　degrees　C　and　25　degrees　C,　respectively,　and　the　EER　were　12.9　and　29.7,　which　are　extremely　higher　than　the　conventional　refrigeration　system.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.